What went wrong in a past relationship?

My last relationship ended because the girl i was with ended up liking someone else and wasin a relationship 2 days after leaving me. That was a year ago or more. And i have to be honest, depending on my mood on the day, i still think i love her. And i know i want her back. I spoke to her for the first time in 8 months a few weeka ago, and shes been with this guy (a different guy) for 9 months now. And im happy for her, i want her to be happy, but of course i wou prefer it if it was with me... However i digress, i guess it failed because im synical, ive been in a few relationships and never said 'the L world' before. So when i realized it was different with this girl and said i felt vunreble, so i made myself distant, i started ignoring her calls, taking a day sometike 2 to text her, putting off seeing her. I drove her away, and i regret it to this day. (It doesnt help that i was a heavy drinker and she saw me get my head kicked in a few times over it, and i continued to drink).

My biggest problem I've noticed at least recently is girls just lose interest in me after a few weeks of dating. I'll be the first to admit I'm not the most exciting guy on the planet. There isn't a much more frustrating feeling then saying and doing all the right things at the beginning only to have a few weeks in start getting ignored or flat out friend zoned because they found out something about you they didn't like. If it gets to the relationship phase. Most I've had have ended pretty amicably.

Things I've Learned From Past Relationships: 1. Too much time with a person is a no no. Give each other space 2. Don't put her on a pedestal, don't baby her. They hate it and this will cause her to think of you as number 2. uhhh what else o_o Things I've learned from my friend's relationships: 1. Dont stress about her cheating. You end up looking clingy as fck and insecure about yourself. 2. Know what you want. If she asks you what you want to eat or watch or do. DONT ALWAYS SAY "whatever you want babe" or "Anything you want". They're asking you for a reason :l I dunno what else, its common sense but I guess when you are in a relationship you get stupid.