Am I exempt from observing Shabbat?

Hello, three years ago I was forcibly hospitalized in a mental health center and had symptoms from the injections given to me more than from the illness itself. I grew up in a very secular home and remained secular. A year ago, I had a psychotic episode and felt as if an evil spirit was tormenting me and clinging to me. In general, I started observing Shabbat and going to the synagogue, but to keep Shabbat, I take 8 sleeping pills and sleep until the end of Shabbat, then wake up. This is detrimental due to side effects. One of the side effects of the injections I receive is heavy smoking, so I cannot observe Shabbat without sleeping on Shabbat. The issue is that I am harming myself, and my mother said that one day I might not wake up from these sleeping pills. The problem is that I have no one to sit with on Shabbat because my mother watches TV all Shabbat, and I am alone, so I fall asleep. In short, I understood that someone with mental health issues is considered a shoteh and is exempt from commandments that harm them. Can I desecrate Shabbat and am I exempt?

You must not harm yourself or endanger your life to observe Shabbat. 

Therefore, you must not take sleeping pills on Shabbat beyond the permitted dosage. 

Try to find an alternative to smoking on Shabbat, I assume the doctor will have the possibility to find an alternative that is permitted on Shabbat.