I'm sorry to hear how lonely you have been feeling. I know before i had my son i used to have many lonely days and evenings, sitting in my room by myself. It got so bad at one point i even got a cat to keep me company, which he did bless him, but it was no substitute. Like you i could make no relationship last, and back then the only people i seemed to attract were the drunks or the drug addicts! Maybe they sensed my lack of confidence and vulnerability, who knows? I wasn't ready to meet someone back then, although i was desperate too, because i wasn't well enough and what i really wanted was for someone to save me and make things all better. Of course a proper relationship is give and take, half and half, you both put into the relationship, not one person saving another from sheer hell. I also sub consciously went for the not so nice people because firstly i didn't feel i deserved any better, and secondly i knew where i was at with them, they were going to be nasty and i expected it. It was kind of like if i was with someone who could put me down to rock bottom, i wouldn't have to do it so much, so although it felt horrible being in those relationships, it also felt comfortable and familiar. I had a lot of issues with my dad from when i was growing up, not being there, or being stressed and unkind when he was there, so i repeated a lot of those patterns too.
It was only when i decided to start building my life up, doing what i wanted to do, building a future for myself, that i was really ready to meet someone. I was on my own for four years with my son (ex was an alcoholic), and in that time i went back to college part time and worked really hard to get myself into uni. I'm now in uni doing a part time course so i can still take care of my son, and three years ago i met someone really lovely. We balance eachother out, he's really optimistic and i'm really pessimistic!, we help eachother out studying for our courses (he's studying too), we help eachother out at home, when he's not there we talk on the phone etc.... It's how a healthy relationship should be, we each give something to the relationship. That's because i took the time to build the foundations of me and my life, and be in a position where i was truly ready to meet someone, and very importantly someone nice who i deserved to be with (not some loser i thought i deserved to be with before).
You will find someone when you are truly ready to. It's hard to trust anyone, i still have some walls up, and he's slowly removing them bit at a time. It all takes time to get out of old habits and patterns, and really have the faith to trust someone, and let them close. I've been hurt badly in the past, and it took me a long time, and a lot to trust someone again.
Keep going out to social things, start by making friends, gradually get closer to them in your own time. It doesn't matter how long it takes, as long as you're always making slow progress and letting someone a bit closer to who you are over time. Take it at your own pace, whatever you feel comfortable wityh. When you eventually have that trust with friends, and make some close friendships, you'll be a step closer to being close with a partner. My partner always says, time takes care of everything
As for grimicing at couples, don't worry about that, half the people walking around are couples, the other half are people grimicing at them lol!!!! I used to be one of the grimicers!