Troubled marriage of 7 years....Hypersexuality, Bipolar and ADHD?

I have been married for almost 7 years to a man who was diagnosed as BP and ADHD.  He also has problems with compulsive hair pulling (though he doesn't rip out hairs anymore, he just uses a tweezers on his beard now).  I am a full time nursing student and have two kids 6 and 8.  My husband is a pizza delivery driver and works third shift.  This leaves me to do everything.  I take care of kids 90% of the time, despite I am a full time student and he works less than full time.  I clean and cook, take care of all the bills, kids appointments, kids school things and on top of it he expects sex everyday.  I am finding that I am less and less attracted to my husband as time goes on because he does very little for me or our family.  He spends hours in front of the mirror tweezing hairs.  He isn't around 3-4 nights a week due to the hours he works, which I have been begging him to change since he got the job.  He used to be a carpenter in the union and quit his job to be a pizza guy, which is completly embarassing and does not pay the bills.  He has refused to get another job, though every few weeks he claims he hates his job and is going to get a new one. He has now been working as a pizza guy for almost 5 years. This job has created many of our problems yet he refuses to even look for another job.  He comes up with an excuse as to why he can't work whatever job is being suggested to him.  He enrolled in school only to drop out after a few days and dropped out of fall classes as well. He says that I am a f'd up person to him all the time because I am "constantly criticizing him".  What he means is that I hold him accountable for all his responsiblities and will not just sit idly by and let him do almost nothing in our lives will I run around like a chicken with its head cut off trying to take care of everything.  Lately we get into these arguments daily. 

He has almost never taken me on dates, doesn't do anything romantic ever, and I mean ever!  He is on meds for ADHD but takes nothing for BP and he sees a PDOC for therapy.  This therapy seems to be doing nothing for him because he is no different than before he was seeing her.  He still feels that I should be uber sexually attracted to him, because he wants sex all the time.  Despite the fact I have told him that it is hard for me to feel sexual towards him because not only am I tired from taking care of everything and being a full time student, but that he does not treat me very nicely, yet he still doesn't get it.  There are times I feel sexually harassed by him because he keeps telling me repeatedly that he wants to have sex with me despite the fact I tell him I am not interested.  He keeps telling me anyway and will sometimes ask for me to get him off despite my telling him I have no sexual feelings for him at that time.  There have also been times when he's been intoxicated and will not leave me alone about it to the point I am yelling at him and go sleep in the living room.  Our sex life was not like this for many years, particulary when he worked normal hours and we were in the beginning of our relationship.

We have seperated twice only for him to "shape up" for a short time and then he of course reverted back to old behaviors shorty after he got back in the house.  I do love my husband but I feel like he is taking advatage of me.  I know that being ADHD and BP has got to be diffcult but I feel like I should be able to expect him to do some things around the house. Because of his hours at his job he is rarely at our kids school events, their sports games, music concerts and family holiday things.  For a long time I keep wondering why am I still married?  If I do everything around the house and he doesn't show up for our kids/family events, what is the point anymore?  Is this what it is like to be married to someone with these problems or is he taking me for a ride?  I am hard working, a very good student and make sure I am at almost every single kid/family event and I take care of my husband.  It's starting to wear on me and I need something to change soon! His strong sexual desires coupled with his lack of doing anything and complaints of me just being an over critical cold hearted indivdual will end our marriage soon if we don't get help! Is anyone else out there that is living this life?? Help!