I would agree with Gravitas
Assuming that finances aren't too much of an issue - a shared experience which you will both remember for a long time would be ideal.
If you can't afford a full Vegas or Mexico thing, then perhaps something local like dinner, the hockey game and maybe going to Brandie's or something.
I really wouldn't suggest getting a lady for him, unless it is something he does regularly himself. Assuming you could even find a lady who would be willing to do a third party booking, you would still have to contend with how he would feel about the whole situation.
I'm glad to hear that you are well on the road to recovery. It certainly sounds as though it was a trial - however - one you have won. Good friends who stick by you through all the tough times are what life is all about.