Need help breaking the cycle.

Hi. I am new to this forum and this is my first post. I have been in a terrible cycle for the past 7 years. I really could use some advice. My family and friends don't understand how hard it is to just leave someone you love so much.
This is a summary of my story. I married my high school sweetheart. Things between us never were good for more than a couple months at a time. I now believe her to be a Narcissist. We were married for a couple of years and things got bad. Since our divorce about 3 years ago we have been on and off.
She is very mentally abusive and manipulative. During our marriage she also got physically abusive which was hard to deal with. Where I come from a man being abused by his wife is considered to be ridiculous. If I were to call the police they would have laughed at me, but it was very serious because she was hitting me on a daily basis and I could not even defend myself. She once broke my front tooth out. After the divorce it has been a cycle. She will return and make me feel like I am the most special man in the world for about a week and then start her lying, cheating, and abusing again. Then when I refuse to help her anymore she just disappears until she knows I am so lonely I will take her back. It is so easy to see what is really going on when we are separated. She just uses me for money and a place to stay. She does not and has never loved me. It appears that she can't love. She knows how to make people feel like she loves them until they will do whatever she wants. Anytime she does something to hurt me such as cheat on me or steal my debit card she makes me feel like it is my fault and I believe her at the time. I find myself thinking "If i was just better she wouldn't have done that." I want to get away but in a weird way I feel if I stick with it I can help her get better. What should I do. I don't want to be alone but I am miserable almost all the time. I am either with her being mistreated or wondering where she is and worrying about her. I need help. This has gone on far to long and I want to be free from this burden.

I find myself thinking "If i was just better she wouldn't have done that." I want to get away but in a weird way I feel if I stick with it I can help her get better. What should I do. I don't want to be alone but I am miserable almost all the time.

You are not in the wrong, she sounds a bit like my ex husband somehow they always manage to make it your fault, when it is sooo not.
You will not be able to 'make her better' she is whatever she is. Sticking with her when she treats you so badly is just messing you up.
Sorry I got to say this but 'There are plenty more fish in the sea' really, there are. You can then find someone else who treats you as you deserve, with loyally and respect. Lots of people do internet dating these days, try that. Work on raising your self esteem.
You already know what you gotta do don't you?
A clean break is needed, yes it will be painful, but not as painful as allowing this abusive relationship to continue.
Be strong.

Thank you. I do know what i need to do. I have done it several times before with her but I always end up picking the phone up when she calls after a few weeks or months. I think I need to just really really try to start dating. I have tried in the past but really I didn't put much into it. I guess I need to be more assertive. I just don't know how to act around women anymore. It sounds silly but its the truth. I don't even know how to talk to women. It's intimidating. When I was younger it seemed so much easier. Internet dating could be helpful though. It is much easier to express myself through writing than speaking.

After being in a long relationship it is hard to start again, daunting, but not impossible. Even harder when you have been abused. You feel battered, bruised and a little fragile.
I starting dating after a 22 year marriage (abusive) I didn't know where to begin. I eventually tried internet dating with some trepidation.
I met lots of different people, mostly nice but obviously you have to be sensible, um, one believed in aliens
I met a good parter, not together now though which is my fault.
This lady of yours is never going to be what you what to be, best move on, don't pick the phone up if its her.