Is Love Really All About Timing?

I am female and 21. My mother has paranoid schizophrenia and my father is an addicted gambler which has brought a lot of grief and problems to the family. I am the eldest of my siblings, so it is only natural for me to take the leading role of the family as both my parents were unable to. Recently I parted with my 3.5 year long term relationship, 'Charley'. I never wanted to stay in the relationship and wanted out after the first few months but he was controlling, manipulative, and most destructively, abusive.
I know I am an intelligent, strong, and caring individual. But having breaking free from what seemed to be a neverending nightmare, it's struck me that my life has changed significantly while being with him and there are more things to fix and pick myself back up from than I first thought. I can't help but feel useless and lost without him. As I watched friends go to university and graduate, I watched myself succumb to his demands and needs. HE was becoming my priority, not my mother or family as it was before. As 'the break up' is starting to feel more and more in the past, I'm beginning to see clearer what my future could be like which brings me a lot of hope and confidence.
The problem isn't the abusive ex leaving a scar. I'm begining to believe that I may be a dependant person, contrary to what I've always thought to be. Due to the nature of my family and my responsbilities while growing up, I think being cared for is what I yearn for. I feel that I want to be in another relationship. Be it destructive or not, I want to be in one. My logic tells me to concentrate on myself and get back into education or work - or to at least heal the wounds of what he has done before jumping into another relationship.
I'm not sure if this person, 'Billy', has just came into my life at the wrong time. Billy is a friend of Charley's, who was in the same uni as him. At one gathering, while I was still with Charley, I began to talk to Billy and learned that he had a mother who was suffering with Alzheimers. His mother is at the stage where she cannot speak and is being looked after in a caring home. This was where I began to speak to him as support for him, as he was clearly going through a lot of traumer and it began to take a toll in his education and life. We emailed and discussed a lot of personal things, all which made me realise we were both incredibly alike. However this whole time I hadn't of considered him as I was stil with Charley. As time went by, we kept using eachother for support. Then I broke up with Charley as things got sour when I found texts and messages from another woman, and it made me question myself whether I will keep being manipulated by him to get what he wanted. It was hard leaving, but he also realised he didn't need me, so he broke it off before I could say anything. I still care for Charley but I know it's for the best to leave such a destructive relationship.
Me and Billy carried on talking and both of us still endlessly chat about our mutual emotional anecdotes about problems in our lives. At the moment, I can feel that we should be together as I haven't met anyone else who shares the same experiences and personality as me because of what we have been through.
I can see myself with him, but I don't know if it's because I've just got out of a long term relationship, because I am dependant on always having a relationship, or because Billy really is the right guy but came at the wrong time.
Should I concentrate on myself and possibly lose the guy that could be the one? If I do try a relationship would he reject me as I am his friend's long term ex? Or I am just desperate for a partner? :( I hope it's not the last one as I know i'm better than that.

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