isabelleT--
welcome!
There is nothing "mean" about taking care of you.
Questions about trust and can you believe him? etc. are tricky - when we break out of denial and accept the reality of how our A loved ones have been lying and deceiving us and themselves it can be a pretty rough wake-up. Be gentle with yourself - calling yourself "mean" probably isn't a very useful tool for making your decision. Do you have a healthy impulse to stay in the US for your own peace of mind and mental health? I'd say go for it!
As far as his recovery - it is 100% his to own.
If he's serious about recovery it will not matter (to his recovery) whether you are away for a while taking care of you.
You didn't Cause it,
You can't Control it.
You can't Cure it.
peace-
b.