I was really weak when I started.... in 2008. I was so weak and frail that I remember talking to my lifting buddy at the gym saying I don't feel I deserve to be in a room full of buff guys. He said no one cares, and that's why you're here --to get like them.
Now, years later, strangers compliment me when I'm repping 335 on squat, or deadlifting 395 for reps. The keys are:
1.) Show up every single day you're supposed to. Even when you're tired, busy, sick, hungry, light-headed, or not in the mood. Heartbroken? Go lift. Migraine? Go to sleep. Too busy? Carve out time.
2.) Track your progress: the biggest key in not feeling like you're spinning your wheels is seeing just how far you've come, and the best way is to track your progress. Take pictures periodically, write down your numbers/stats.
3.) Seek out inspiration for me the biggest motivators were what appeared to be vain/ negative thoughts: I want to lift to look better; I want to lift because I hate failing; I want to lift because I want to be the strongest guy in the room. Whatever motivates you then use it to your advantage. The biggest motivating feeling for me is spite, so I've learned to use that. My buddy is overly competitive so he uses that.
4.) Diet: this is one of the biggest ones. If you're bulking then I GUARANTEE you're not eating enough. Guarantee it. Also, you don't need to be rich or even decently off to bulk. Heck, just yesterday there was a documentary released called "Lift the World," that shows just how accessible the sport is as there are lifters featured who aren't sponsored pros. Check out /r/EatCheapAndHealthy and /r/budgetfood for tips. Also, there's the $50 a week for bodybuilding dude. Heck, all you need is eggs, potatoes, oatmeal, and chicken, and you can find those super cheap.
If you're serious about it then you'll find a way to accomplish it --trust me. Just seek help, keep track, and be consistent. You fall down, pick yourself up, and keep lifting. Don't stop just because you missed a day or a week or even a lifetime. Just lift.