I understand the feeling. Remember that being strong and "growing up" don't mean doing everything on your own... I believe the real strength and maturity is knowing when to ask for help and being able to do so.
That said I also understand wanting to be cautious with your mom but I am glad you are not keeping her outside the loop on this. She has your well-being in mind, and she is right in wanting to make sure that
you don't end up hurt by all of this. Although she may wish that you would break contact with him... I understand that you don't want to do that (and that probably wouldn't be in your best interest either... he is a friend and you have to do what you can to help) but the other extreme would not be healthy either. You do have to find a balance where you can care for him and be there for him, but not take responsibility for his health, nor let it consume your time and energy. Hopefully you can let your mother's warnings be a reminder of that and not become angry when she makes suggestions.
When I was in similar situations I had friends who knew of the situation but were not involved in it. When a problem was eating into my time and daily routine I would regularly go visit these friends after a long day helping someone with stress and grief... and it gave me a way to "decompress" at the end of the day. I would go there every night, sometimes just talk about it a little, sometimes let my feelings out that I had to hold in during the day, but most of the time just unwind, eat, converse, watch TV with them just to regain my balance.
I was lucky to have a "network" of trusted friends back then to help me in that way.
Even just taking some time as a break, to see a movie or something, so that you are not thinking about this 24/7. It may be too early to do this now since it so recent but as time passes and things ease up try to treat yourself a little bit. You do deserve a "reward" for being such a good friend... a reward in the sense of giving yourself a break and some time to catch up. In the meantime seeing a counselor is a perfect idea.
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-- The world is what we make of it --
-- Dave
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