first, this is a throaway account (obviously).
so to answer your question, i could probably go on for pages and pages explaining how i got here and why it is unlikely to change in the foreseeable future, but i doubt you want my entire life story, so i will trim out most of the details. however, the reasons are complicated, so there is no adequate answer that is truly short.
first, i was raised in an extremely verbally and emotionally (but not physically or sexually) abusive household. dad is an extreme narcissist, loves to control everyone around him, mistreats retail clerks and restaurant servers to feel big, treated his wife (my mother), my sister, myself, and his 2nd wife (my stepmother) all like complete crap. lots of screaming fits over common, mundane ordinary events that were beyond our control, such as bad weather, traffic jams, or hating his coworkers. dad was 6'4" and 300 pounds, so his temper tantrums were terrifying. lots of screaming for us to come running to his beck and call at any random time to fetch him things, and more screaming if you were not at his side literally in 5 seconds or less. i had learned to jump down 4 stairs at a time by the time i was in high school, just because of his screaming. zero privacy. he would burst without warning into my bedroom at any time, day or night, as well as into the bathroom while i was showering or defecating. he walked around the house completely nude almost every day, and enjoyed how powerful it made him feel to make everyone else uncomfortable. he demanded sex from his wives as if they were required/expected to pleasure him regardless of how badly he treated them. consent under those conditions has to be questionable at best. dad demanded extremely high performance -- straight As, AP classes, multiple co-curricular activities, leadership positions, etc. zero time for friends or even sleep, and the few friends i was allowed were all subject to his veto (which derived entirely from his arbitrary prejudices, and filtered good people while encouraging me to hang out with potheads who were simply good at appearing responsible). dad regularly neglected our pets, including in ways that i later found out were criminal neglect. he denied us access to health care, even though we could have afforded it with a few minor family changes. he lied any time it would gain him an advantage, especially to his boss and to clerks in stores, and he routinely verbally accosted me for not doing the same.
he was a supportive dad, but only when it was something he wanted, like the aforementioned grades and activities. he actively suppressed anything i wanted to do or be, like to become a compassionate person, help people, spend time with friends, or practice art as a hobby.
mom was raised in very poor rural agricultural region where children were basically free labor and property of their parents. she felt my sister and i were very lucky to be allowed to attend school instead of manual labor like she did growing up. children should remain silent and never complain. the key to any punishment was to make sure the child was utterly demoralized to the point of deep and permanent shame so as to guarantee any misbehavior was never repeated. she made me take down my pants and underwear for a spanking in front of my sister when i was 9, exposing my genitals. i will never forget that. any consideration of a child's feelings inevitably led to spoiled brats, and her job as a parent was to guarantee her kids were not spoiled. she even took it upon herself to discipline random strangers' children in public, such as in restaurants or grocery stores.
i am a skinny and weak male, and needed vision correction from a young age. that means the favorite target of bullies. remember mom, who feels children should not complain? yeah, complaining about bullies at school resulted in punishments and lectures about how being the victim of bullying was my fault (i guess i should have somehow stopped boys who were twice as strong as me and tormented me in numbers). remember dad, who was a bully himself? complaining to him resulted in him "showing me how to stand up for myself" by physically attacking me, a 120 pound 12 year old at the time. yeah, if i were 6'4" and 300 pounds attacking a terrified skinny 6th grader whose entire life i controlled, that kind of tactic would work for me too, but then i wouldn't be targeted to begin with.
clothes were often home made or goodwill. sometimes walmart if i was lucky. they never fit, because my body was way too lanky for anything off the shelf, and i shot up in height so fast that even the home made clothes didn't stay fitting more than a few months.
so those were the people i learned my social skills from as a child. by the time i got to school, i was an anxiety ridden mess. this fucked up any chances of making friends. the resulting social exclusion just meant i never even had a chance to learn different relating skills than the toxic bullshit of my parents. by the time i was old enough for dating, combine my skinny weak body, my glasses, my horrible social skills, my second hand poor fitting clothes, and of course there was nothing for middle or high school aged girls to feel attracted to. some even felt sorry for me and were nice to me, but of course i couldn't expect them to commit social suicide by actually dating me. and there was no money or freedom for dating in any case, because dad controlled 100% of the time, and any money earned in my summer job went to dad to help pay gas an insurance on his old junker car i used to get back and forth between school and activities.
i went on to georgia tech, an almost entirely male school, flunked out in year 2. was just so anxiety ridden that focusing on school was impossible there. dad had been threatening to kick me to the street since i was 13, and fearing he would do it when he found i had flunked out of college, i asked mom to take me in. she did for a short time until i could get my shit together and move out at the age of 23. i have been financially independent for the last 17 years, never needed any money from parents, built a career, returned to college and finished my bachelor's, recently bought a house, have 2 loving cats and am still an anxiety ridden mess, with a healthy dose of depression added in due to decades of social isolation.
my anxiety is severe enough that it is very hard for me to share living space with anyone, which, coupled with my career being built entirely on a high school diploma (my bachelor's is finished but only qualified me for the job i was already in), has contributed to low pay and high mental health care costs (the icing on the cake is that my employer has rather shitty health insurance, and the aforementioned anxiety makes it more difficult to find another job). all of that has resulted in a very limiting financial situation. nearly all of my money is going to fix up the small, somewhat messed up house which was the best i could afford, so there isn't money for the activities most people think of as dating, and i feel guilty any time i spend even a little on myself (which could go to fixing the house).
so as you can imagine, between my body, my finances, my mental health, and my underdeveloped social skills, i just cannot imagine that any woman would want me. since i don't believe any woman would authentically want me, i am very suspicious of any hypothetical woman who would claim to feel attracted. i would suspect she is either acting out of pity, or sees some opportunity to use me (though i don't have much money, so the latter doesn't seem likely). i have never been wanted for myself, so i just don't see how such a thing could even be possible.
the whole thing sounds like i am just feeling sorry for myself and not doing anything to improve. to some degree that is true. i do feel sorry for myself. and i could have done far more to improve than i have. but i have done some things, and everything i have done has been done in isolation, absent external support, and while coping with severe anxiety and moderate depression. i finished my undergraduate degree summa cum laude while working full time, built a career, bought a house, established good credit, and have been a far better dad to my 2 fluffy kitties than my own dad ever was. but that still puts me far out of range of the healthy, strong, attractive, and financially secure man that women actually desire. i'm sure a sufficiently desperate woman would settle for me, but i would rather remain single than be the man a woman settled for. i need to be actually wanted.