I just want to say how wonderful It is that you have stepped in to help your neighbor! My husband of 22 years died in October just over two years ago so I know how very special it is to have a caring person like you around at a time like this, especially when there isn't much in the way of family to help. Thank you for having such a big heart.
I think your idea of a support group is a good one, from what you have said a non religiously based one that will give him a chance to talk about his loss, learn that he is not alone in his loss, and involve him in some activities. Men tend to make friends by doing things - sports, working out, building stuff, etc. while we women make friends by talking (the guys talk they just have to have some activity going on to make talk okay) so maybe through a support group he will come into contact with people to engage in activities with. Good luck with this, his loss is still pretty fresh, I know that I was still swinging back and forth between numb tea timers most of the time at that point, and my husband died after a long illness so I knew it was coming and thought I was prepared.
I also love that you are taking food to him, that is very thoughtful. I would suggest that you may want to keep this to two or three times a week (plus sharing baked goodies). The long-term goal is to have him back on his feet functioning self sufficiently. Someone needs to introduce him to the wonderful world of frozen meals. Marie, Stoffer, Healthy Choice, Smart Ones, Lean Cusine, etc put out an incredible array a meals today that are tasty, take only minutes to prepare, and clean up means washing the fork and throwing everything else out. What I'm trying to say is it is really sad to cook for one and it is easy to come up with excuses not to do it, but with a good selection of today's frozen meals in the freezer those exceeds just don't work.
Beas wishes, I hope everything goes well!