Mine is fairly minor compared to others here. She was my friend for 5 years, and I always liked and admired her. Her boyfriend left her, treated her badly. A few months later I told her I liked her. We hit it off and began dating and things were great for 2-3 months.
Then her boyfriend came around and she began talking to him again. Now, this alone is kinda weird, but my relationship previously ended with my SO cheating on me. So I was a little anxious. When I talked to her about it she laughed it off and didn't take it seriously. When I brought it up again she did the whole "What, you don't trust me?" nonense. By this point I'm having some red flags pop up in my head, but I really did trust and care about her. I loved her. She was beautiful and intelligent and my 5 years of friendship before she always seemed like an honest and good person. So despite my gut feeling and what others warned me about (when I talked to them about it) I resigned to trusting her. They were just friends. That's all. Totally.
As time went on the following few months she became noticeably more distant as we began seeing each other less. I checked her phone at one point and saw she had been talking A LOT with her ex, and while none of it was expressedly sexual or flirty I got a bad vibe from the tone of the messages (and frequency of her emote use...).
Last December we were supposed to have a special weekend together the weekend before Christmas. We both felt the relationship was weak and we were trying to fix it. I began texting her to meet up on Friday and she says she's busy. Busy what? Finally she says her ex contacted her and she was hanging out with him and we couldn't do anything. This finally pissed me off and I snapped at her about it, but I apologized for it. I still cared about her and wanted to have a special weekend with her. She denied it, seemingly angry at me now and our 'special weekend' became an hour phone call on Sunday.
She broke up with me on January 23rd. She flipped out on me and accused of me being jealous all the time. She claimed I was gaslighting her. She proceeded to block me everywhere and I have only talked to her a few times since.
Anyway, yes, a few weeks after dumping me she began dating her ex again. She insisted she never used me or lied or did anything wrong, that she left me for 'being a jealous manipulator." Apparently, according to her, there was zero correlation between her more actively spending time with her ex, less time with me, and her leaving me for him. The last month of us dating she became verbally abusive, insulting me directly (idiot, moron, an autistic fuck, etc) while also mocking me as a man ("geez Nerevar, I thought I was the girl in the relationship"). She trivialized my feelings and was negligent, using, and completely self-centered for a majority of our relationship. She took money and support from me, was controlling, bullying, and seemed to project a lot of her issues onto me.
In hindsight I obviously realize she was a shitty person and I was an idiot for ignoring the red flags. But I really did love and trust her and she took full advantage of that. The drama and anxiety really stressed me out during the relationship and the months after that it affected my weight and caused hair loss. But she didn't care. She got what she wanted at my expense.
I both miss and hate her.