Should I Break up with him?

So here's my story. My current boyfriend and I have been dating for a little over three years now. It was super awesome at first, but it's gotten stale. He has no job, and isn't really looking. We live together in his friend's dad's basement because I can't afford to support both of us on my minimum-wage part time job. I feel like he doesn't have any ambition or is just afraid to grow up.
Somehow our relationship has soured on my end. I am not attracted to him 90% of the time, either physically or emotionally. He is so codependent it almost makes me feel more like his mother than his girlfriend. Recently he went through a serious bout of seasonal despression (as is the case with every winter) and told me that not only did he think he was still in love with his first girlfriend who is now a lesbian, but he became very suicidal. He has gotten blackout drunk on a few occassions and been very abusive to me, but always cried and been very apologetic the next day.
I care about him, but I can't fight him for his life and I feel like I'm the only source of his happiness. He just doesn't make me happy anymore. We have good days still, and it makes me second-guess myself. We cuddle and laugh together, but a few days a month isn't enough for me. We don't really have screaming matches, he just refuses to talk to me everytime I bring up something serious.
And another big reason I want to leave, besides not feeling this relationship anymore, is that there is another guy who I have had a crush on for a while who has expressed extreme interest in me.
I guess I'm scared to let go of my current BF. I don't want to hurt him, but it's killing me to stay. We've been through so much together, but I can't act like a businessperson throwing money into a dying business anymore. And I'm afraid if I do leave that this new prospect won't work out, and I really want it to. My biggest issue is that I won't have anywhere to live if I move out. I can't afford my own place, and I hate being a mooch. But I guess that's not such a big deal, I've lived in my car before and I can do it again.

You seem to know the answer. Go do it.

Your relationship sounds terrible. Get a full time job so you can GTFO.

Also, forget about the other guy for now. Your future prospects should have no bearing on whether you stay with this loser or not.

I can relate so well to your situation!!! My sister had been with her boyfriend for 7 YEARS! He has been living with us for 5 YEARS. NEVER HAD A JOB, HE IS ALMOST 30, AND SHE WORKS TO SUPPORT HIS ASS ALL THE TIME AND THEY AREN'T GETTING NO WHERE IN LIFE. My parents have been supporting this habit because of fear of loosing their daughter. They fight all the time, drink, and come home and always argue and i get so frustrated, Many times i kicked his ass out. My advice to you is that if he doesn't have any ambition and if the love isn't there anymore, honestly do what you have to do for yourself because at the end of the day you only have certain chances in life in order to make something of yourself and your future and yes it would be great if you had a second pair of hands who has the same mentality as you and strive to be somewhere in life. Don't hurt yourself over this guy, and honestly if you break up with him which i hope you do, IT WILL make him understand why and hopefully put some shoes on his feet to step up and do what he has to do. Sometimes people have to get hurt in order to under stand and acknowledge and learn certain things. If you are scared about hurting him, then what about yourself, I am sure you are hurting yourself. I didn't leave my ex even though i wasn't happy in fear of hurting her and in the end what happened? she left me! Do what you gotta do and leave! The only thing in this life we are 100% certain of is death. Please revise the issue and do the right thing. Hope this helps!

RUN< RUN< RUN!!! I have had relationships like that, where they begin great, but then the guy gets lazy or stale, or whatever the case may be. If you stay around for him, you are only depriving yourself from true happiness. You can't live for others and you always need to make sure that you put yourself first. I know this sounds selfish, but if you don't, you will end up becoming a door mat and you will lose yourself and then you will become depressed.

I wish you the best!

"No need to be coy Roy.... hop on the bus Gus.... set yourself free Lee"