Just to quickly say, I haven't read all the responses because I started writing this a few hours ago and went away and came back to it.
I think that I used to be a bit like this - just needing to be in a relationship rather than not. But then I was so miserable with XP (controlling relationship) that I was just glad to be on my own when I left him and have that freedom to do whatever I wanted, it was such a relief that I was happy to be single. I can honestly say I am much happier being single than in that relationship.
So once I realised that being single was better than being in a bad relationship, I decided that any relationship I had in the future would be on my terms - it's a relationship, not a contract. I should only be with someone if they make me happy, and I have the right to walk away at any time if I am not (for this reason I realised it will be a LONG time and take a VERY special person before I will ever get married, because I think that is more of a commitment - a contract if you like - and I suppose I didn't see it as seriously before.) I am not saying that if a relationship goes through a bad patch that you shouldn't try to make it work, but that you should take things really slowly and make sure you really want each step before you go to that, and it's ok to take a step back to give yourself some space. XP moved very quickly when I first got together with him, and looking back I was not in a great place at the time - all hallmarks of a controlling relationship, I didn't see this at the time though.
I have also come to realise that what I thought before - ie that good men were few and far between - isn't necessarily true, and there's no point staying with someone because you think you'll never meet anyone as good again. And there is no point staying with someone just until someone better comes along, because A, that's not respectful or fair to the person you are with, and B, you're never going to meet someone decent like that anyway, because most decent men will back off if they think you are with someone.