My Boyfriend thinks he's going to die soon....

My boyfriend and I have been together a little over 4 years now, we've been engaged for 1 year, and have a 1 and half year old baby girl. Going through our whole relastionship he's had his ups and down in his health. The main one to bring me to write this is his Seizures. He's been dealing with them since he was 2 years old, he went a long time without them causing him to no longer need his meds. I didn't see one first hand until 2 years into our relationship, they were every few months and it continued that way. He would be good a 2 or 3 months then have another one. He's recently gone threw alot of stress and it caused us to separate for a whole month, but we've been back together since the 7th which is went he had the worse seizure yet, He collapsed at work and was told he wasn't breathing for 2 minutes. I went and stayed with him in the hospital, cause he absolutely hates them from having to grow up in one, cause how bad his Seizures were as a kid. So after the 7th he had one the 10th, then two the 13th, another one the 14th, then recently one yesterday the 16th. His neurologist told him no more work his appointment the 15th, he's only on Keppra for seizures, he was on 500mg, but not they bumped it to 750mg. He's also taking Amoxicillin 875mg for an ear infection and Sertraline 50mg for depression. I don't know anything about medicines, but I'm doubt his mixing these are doing any harm to him. Each time he wakes up from one his body mostly his legs are completely numb for a few minutes, and he physically feels sick, I know obviously cause it's a seizure it's gonna mess with him no matter what. He always tells me after having one how he's not going to last much longer and his times going to come soon cause he's been dodgeing death for to long now, I believe it's mostly his depression talking, but it tears me apart to hear it and see what he's going threw right now. I'm shaking evertime he's away cause I never know if he's okay or not. He's had his 2 different days while away from home. He still has on going test being done of him and more appointments. He's signed up for SSI. I can't cope with the thought he's gonna pass, I've made myself more stubborn that I won't take no for an answer anymore that if he has a seizure we are going to the ER. I can't get him to stop smoking, I know it probably isn't helping.I need any advice and support cause I feel so overwhelmed.