As far as attitude goes, I actually am somewhat different from your son myself, but I am close to someone that has this sort of attitude and actually I have stressed before very much about how I can help this person who at times seemed to be a black hole of negativity and hopelessness. It seemed like it was impossible to be of any help even when I knew I had such positive intentions and was so willing to help. Over time I actually have learned to help this person and actually the most important factor in being able to do that was to learn to pull back. When I was always trying to re-frame things to be positive and optimistic, it never helped.

You know, some people actually find comfort in negativity and low expectations. Usually this means they have very high standards for themselves and find it hard to live up to those standards. It's a fear of failure, then fear of failure leads to fear of action. You definitely can't change the fear, though I can completely understand why you would want to. Sometimes it's even just a tendency of their personality.

I think it is actually important to not try to change the negativity. It's good, for example, if he were to feel more like he can talk about it and vent about it. It may seem unreasonable and excessively negative to you, but, the negativity may be a source of comfort for him and it's important not to try to disarm him of that. Think of it like a child's favorite blanket. It's not like it will never change, but maybe he just needs that right now. I'm not saying to agree with it, it's okay if you think he's wrong, but really, nobody is going to change his beliefs. If those are ever going to change, that needs to come from within himself. It's okay to disagree, but there is a difference between disagreeing vs. needing him to agree with you. Correcting him only feels like judgment and then creates distance. It's okay to care and okay to be concerned, but don't let it get under your skin too much. Don't let it change who you are when you're around him, because if you change he will feel it and it will only make him more skeptical of your intentions. Appreciate your son's positive traits, but let him decide how he wants to utilize them, and don't try to spare him from failure, because I think the one thing he needs the most is to learn to be comfortable with the notion of failure. It's really okay to fail. Failure offers wonderful lessons, and the most successful people in this world are those who have failed routinely, because they learned the most. Now look at, for example, if you were to say "I would encourage you to do this or that thing because I want you to succeed," in that you are also sending a covert message that "I am afraid you will fail without my guidance."

It's probably hard for you to pull back when the state he's in is so genuinely worrying, but I think it's all you can do.

Hopefully that's some more food for thought. You clearly care and your heart is in the right place and you just want to help him, I know you do. I think it's just a case of everybody having different needs and really, a different mindset. But there is value in each of those differences. What I can say for sure is that nobody ever got worse by being listened to and heard without judgment, even IF what they're saying sounds completely untrue and unrealistically cynical.