DS1 is 17 (yesterday!) and he has some of these traits, although not quite as bad as you have painted your son. However, he does seem to take responsibility for what he's doing at college, so I can't complain on that front.
Some of the things you have posted, though, worry me - about not wanting to confront him. I suspect that you don't like the whole telling off/shouting/'losing it', as you say - but unless you really do express your feelings then he is never going to really understand your anxieties. You seem to have relented and let him off too much, IMO. (Sorry if this sounds harsh - not meant to be)
If he's really not that bothered about college, then it might be time to let him give it up - but on the understanding that he goes out to work, and pays you board.
Can you talk to his college and see if they would allow a year out? It maybe that it will take him having a year out, working, for him to realise that college is a better place to be.
My DS is lazy too, but has to do certain things - because we have made it clear that it's non-negotiable. We still have to nag/shout/worry away at him, but he does do them - eventually.
One thing I would really recommend, though, is that you cut off his source of funds. Stop paying for all his things. If he hasn't got the money then he can't go out. If he hasn't got clothes, then tough.
I think you need to get tougher with him, to be honest. Toughen up yourself too, and stop avoiding the confrontations with him. You are his mum, not his best friend - he may hate you for it, but unfortunately that's the role that - at the moment - you have to play. He has to deserve your approval.