Teen lonely

Oh, that sounds sad. I guess if it were me, I'd try to find some sort of youth center or something.
As his mom, you can't really help him make friends when he's seventeen years old, but you can help him find places to be where there are other kids his age, so at least he has something to do and someplace to go instead of sitting home by himself.

Most cities have some sort of youth center, don't they? I know they do over here. It's just a gathering place where they have sponsored activities that appeal to kids . Look in the yellow pages or call the town municipal center and see what's available.

Good luck.

Is he athletic?

join a YMCA.

Does he have any hobbies, if so join a club, some after school activities or something like that.

I think he should look for a job -- that's always a great way to meet people, especially if he's kind of shy and has a hard time putting himself out there in different situations. With a job he has some place to go and people to interact with.

Joining any sports team would help to make friends,
music or theater groups and anything else offered through school.

This is a tough one, but I would do nothing. He's 17 and soon you won't be able to hold his hand for him. Toss a few ideas his way and let him run with them. That "get a job" recommendation sounded pretty good. In a couple of months he'll be in school (assuming he hasn't graduated) and he'll be the new guy and get plenty of attention. I'm sure it was hard to leave his old friends behind, but this could be a good growing opportunity for him. Of course that doesn't make it any easier to watch.

Tell him
"If its to be, its up to me"

Im soon turning 15, and i can kinda imagine how it would be having no friends.. No people around my place, has an interest in rap, so i stay alot for myself, and i'm actually fine with being alot by myself.

I guess as a mom, you just wanna do ur best, but i think, that you should just like... let it flow.. you know?

When I was fifteen I was one alone kid, none that I knew of in the neighborhood and my school was quite far away, two bus trips.
The day I turned sixteen, I got a job at the local hospital, and my life turned interesting.

I don't know if that is possible anymore, but something like that, or volunteering, could be a good entrance to real life.

Tell him to spend time doing the things in which he is good that may be anything like painting, photography, dancing, cooking, etc.
Best way is to go out know the new world the people around and friends will be automatically going to happen.
Life is nothing if you are waiting for right things to happen , you have to do efforts to make it right.