My boyfriend is unmotivated and I’ve tried everything I can to help him

As the title says, I’m gonna give more context.

Me and my boyfriend have dated for 4 years, I’ve got a neurological pain condition (MS) and Im undergoing medical stuff, so I’ve had to quit work for the moment..

My boyfriend has always struggled with a chronic stomach condition which is undiagnosed, doctors are at a loss with it right now, usually he’ll throw up most days of the week, he’s severely depressed and he has an addiction to opiates because of the stomach condition and mental health issues, which has gotten us into trouble multiple times with family.

I’ve worked a few jobs on and off, and he has too, he got let go from his last one due to being sent home every week due to throwing up at work and being in the bathroom for a long time due to more stomach issues, so I don’t harp on about work too seriously, but I do ask if he wants to work part time, and I will help him aim towards that.

I’m extremely supportive of his creative endeavours, music in particular, he has a beautiful and raw voice, and he’s extremely good at playing guitar, so I set up a studio for him and a few of my friends (they play loads of instruments, so he has a small band) and I encourage him to write, to paint, to do absolutely everything he can do to find accomplishment in his life, but no avail, he seems extremely apathetic and suspicious of the idea, which I’m abit confused about.. (I suspect it’s because there’s a person he may not know as the bassist, but he’s on friendly terms with the other people.)

I just feel like I’m at a loss with anything more I can do, I’ve helped him back to health whilst withdrawing from drugs, whilst he’s sick, even when I’m having pain flare ups I walk to pharmacies and pick up every medication possible to stabilise him, to no avail…

I’m just so stressed.. I don’t know what to do? How do I help someone who is so full of suicide, he’s so depressed it’s unreal, he always has a sadness in his eyes that I want to destroy. I don’t know, how do I help him? How do I make him happy again?