Seizures Interfering With Love

My husband and I have been together for 15 years. We have been married for 8 years. I'm 38 and he's 42. He and I met when he moved into an apartment next door to me. We dated for about 6 months when he told me he had tried to commit suicide 9 years earlier and, as a result, had been in a coma for a year and had head injuries which required him to take anti-seizure medications. My past experiences helped me accept his past. Although he was taking the medicine, he didn't have a seizure until four years after we were together. The second seizure came about a year later. We married about a year after his second seizure. At that time, his seizures became more frequent and started presenting problems for him. He was not able to maintain a job and had to miss quite a bit of work. Up until that point, he had a good job and we were financially secure. When he began having seizures every week, I was forced to make more money. My salary has never been enough to really support us both and financial problems have been constant. In addition, he has become more dependent on me and his medication interferes with his ability to concentrate. His behavior is often irresponsible and I'm certain that the combination of Topomax, Dilantin and Depakote affect his ability to think clearly. He lost nine jobs last year. I do love him, but I no longer feel like his partner. I feel like a mother to him. I am not sexually attracted to him and I hate myself for it. I care about him deeply, but I long for an intellectual, mature relationship. I have already had an affair and it made me physically ill. I couldn't maintain it, despite the intellectual and sexual aspect. My conscience won't let me leave him, but I don't know how to stay with him and feel satisfied. I don't know if this is even fair to him. I don't think he could survive without me at this point. I don't know what to do. I want to do the right thing, but I want to be happy. I want him to be happy too. I appreciate your listening to me. I've sought professional help, but haven't really received meaningful advice. I understand that my problem is not an easy one to solve, so I don't blame anyone for not being able to help me. Thanks.