Wife has nocturnal epilepsy, please help!!!

Hi thanks for reading my post...I am in need of some helpful advice I have been with my wife for 8 years. She had siezures when we met but her family never helped her get treatment for it. So I did and she was given disability income for the time she had worked. I was assigned as her payee. I have taken on the role of care giver and helping her have a decent life out of homelessness for most of the time we've been together. When we met we were homeless and since I wasnt into alcohol or drugs we were able to make some good decisions together and get out of homeless for a time. She uses marijuana heavily to control her seizures and symptoms, and was born in a house where tobacco was smoked around her as an infant and by her pregnant mother. So she uses tobacco way more than I do. I am having a hard time feeling like I can assist her and be happy in our relationship. I worked so hard to help us keep apartments in horrible places like las vegas and southern california, to buy her overpriced pot in cities where i would get bullied at work. Our relationship has had some good moment but has been consumed in struggle, from getting out of homeless to finding some kind of way to bond together other than with cigarettes and pot. I grew up in an abusive household and never got help or acknowledgement for it, really. I am the only person in her life, neither of our relative are helping us and now we are homeless in a van trying to find somewhere we can work for room and board so we dont have to keep sleeping in parking lots and spending all our money on gas. But I have been having nervous breakdowns lately...she doesnt want to be an athletic active person the way I do. She would not explore spirituality or intimacy with me, when I presented it to her in more stable environments. I am beginning to hate this van, and feel like I am at the end of my tolerance of misery for this relationship. It feels like we do not even live togehter, like we dont eeven survive we just struggle. I feel like I am not enough to help her, and that makes me feel so worthless. At times I feel like her younger brother, and we were both abandoned by our parents and im the only relative shes got left who will help her. We tried to have a baby togehter while settling down and they took our first born child our daugher away becauase of Katy's epilepsy they said it made her an unfit mother. I feel that nothing i ever show her will help her feel that she is happy or her life is complete, becasue her childd was taken away so cruelly while my relatives did nothing to assist even though they were aware of the situation. I am questioning my sexual orientation as well... I feel that I have been changing for the whole 8 years of our relationship while shes stayed the same and weve grown apart. I coped with losing our child through spirituality and meditation. Even if we were to separate, we both have nowhere to go and there is only one van between us. Sometimes I feel that I have to go to the nearest social services offfice and tell them whats going on, to call social security and resign my status as her payee. I dont know what to do have nobody to ask for help and no relatives or mentors to guide me. I am tired of cigarettes and pot and feeling my body get weak by her side while we continue not doing much together but smoking. There is more too this but I hadd to get it out....if you read and respond at all I appreciate you very much and will read it... Hopelessly yours Struggling in a Van