Emotional/Verbal abuse..Why do I keep returning to this abuse??

Lately I've been searching to better understand myself and the choices I've made with my relationships. I'm 24 years old and I feel emotionally drained and confused. I found myself browsing and reading post after post, and couldn't deny my similarities with many of the feelings expressed. I figure I might as well just post my story in hopes of some type of advice, or new realization that I have yet to hear/read.Here goes...

VERY long story short...I have been involved with my high school sweetheart/not-so-sweetheart at times, on and off for 10 years now. We are polar opposites in most aspects of our lives, with some similarities, but we can't seem to leave each other alone. I love him no matter what, but I know that doesn't mean I should stay with him. At this point, I realize that the best thing I can do for myself, and hopefully for him is to cut-off all contact. It hurts me to stick by that, but I can do nothing else. He and I are very different. I would never hurt someone by name-calling or shouting hurtful words. I believe that you should treat someone the way you would want to be treated. I'm an optimist in ever sense, and he has a pessimistic view of life.

It was during high school where I noticed the short temper and foul mouth of my bf. Coming from a sheltered upbringing, this was new to me. It didn't get too bad till our senior year when we began arguing and fighting often. Bad habits, but I couldn't let go of the feelings. Also during that time my parents split, and my mother decided to begin a separate life on her own. I hid my feelings towards this but confided only in my bf, because many of my friends and other family had no idea this was happening. It was unexpected, and strangely my siblings and I went about living our lives normal, as if this weren't happening. Looking back I believe that this separation has much to do with my attachment to my high school bf.

After high school he and I ended our turbulent relationship, because I went away to college. He and I were both heart broken, but I eventually blocked it out and moved on. We stayed in touch and had respect and love for one another. I had a new healthy loving relationship. It was complete opposite of the one I had before. Yet, as time passed I grew very homesick and decided to transfer to a college closer to home and my family. Times got tough. I began to recognize and deal with depressed feelings I had towards my mother. It was as if it all of the sudden caught up to me. I felt alone and unhappy. I thought I would look in to counseling on campus before I transferred back home. After a few sessions, I found it difficult to let out feelings and emotions, so I kept much inside. I also noticed that I wanted to call and talk to my high school bf afterwards. It was comforting to speak with him. I eventually moved closer to home, and broke the heart of my college boyfriend, which I felt terrible about. I didn't understand how my feelings for him went away. I didn't know if it was a natural occurrence, part of this depression that was occurring, or a realization that I didn't fully let go of my high school love? I was confused.

Fast forward a few years and I am now graduated(thank God) and am starting grad school soon. My relationship with my mom is still very limited and far from healthy but we speak which is good. Sadly, my high school boyfriend and I have been seeing each other ever since I moved back. I say sadly because, at first it was great. I felt feeling in my heart again, and I thought he was so happy to have me again. I thought we got our second chance and things would be great! Wrong. Feelings and emotions began to surface as months passed. He confessed how depressed he was after I left him and moved on. He said part of him knew I needed to be happy, but the other part hated me for it. I felt guilty because I didn't even think twice about his feelings at that time, and I don't regret my college relationship, I just needed to experience that. Well, things grew worse and his attitude changed towards me. His anger worsened, and the temper flair-ups increased. He had been/is in college and has his own family struggles that he is facing. I am often blamed for my past and hurting him. Yet, every time I leave he pulls me back and I give in.

Last year, I had found out he had been lying to me about seeing someone while we were on one of our "off" again periods. I was very hurt and reminded of our high school years. I wanted to leave the relationship after discovering the lie and I did for some time. He broke down and said it happened because he wanted to experience what I had in college, while he was home depressed over me. Obviously, I don't think that's fair or healthy to say. I have this weird empathy towards him. I feel like he has issues that I don't have, and I'm the one who understands and he knows it. He is scared to lose me but I feel like he hates me at the same time. Then I think, am I here because I'm scared to lose him? Yet he wants to work it out when I go months without talking to him. Anytime things are okay, we argue about past stuff and lies, and his communication style, or lack thereof, turns into horrible name-calling and emotional abuse. He can't control it, and feels like I "make him" do it. If I didn't say "this" or "that", then he wouldn't flip out and verbally abuse me. Blah blah blah...sometimes I think do I really cause this? I know he has anger and past issues, but do I have issues as well? Aside from staying in the relationship. His abusive language really hurts to hear, even though I've heard it plenty times. The fact that he uses it knowing its going to hurt me...hurts. He smokes pot everyday, which I feel adds to his unhappiness, insecurities, and anxiety. I could be wrong-which he says often, I don't know

These last months he and his family, Mom, Dad, and older sis, have been seeking family counseling to address fighting and arguing amongst each other. They're a loving family but have their issues and are working on them. He has confessed to me that he has a problem and doesn't know how to be happy or how to treat people, and he doesn't want to be this way. I know that. I can't change him, but I can support him. But to what extent? I feel like he won't truly tackle or begin to repair himself unless I leave the picture. It sucks, but I realize I need some happiness in my life, but I worry about him. What if he can't ever be happy? What if he needs me? (<- Was that crazy to say?). I want him to be happy and I want to be happy, but I always end up missing him usually after one month has elapsed (that's the pattern I've noticed). I'm 24 and he is 26, we are young and have wasted these last years battling each other and then returning to continue the battle. FRUSTRATING!!!

Well, looks like I went off typing away all over the place. This was my first post, so I apologize if this is not proper post length or etiquette. Just venting helps.