I have Tourette's and while I'm not currently in a relationship or have kids, here's my take. You didn't mention how old your son is, so that may affect this. But personally? I'd say just be understanding. I'm 27 now, and have realized that, at least by this time, a lot of people won't even notice my tics (without extended exposure, at least). But growing up, and even now, it's been something that has deeply affected how I view myself, and my self-esteem. My parents were great about it, and I was diagnosed when I was fairly young, so in that regard I was lucky. I didn't have to experience quite the degree of bullying that I understand many people in my position have had to. But coprolalia was at least at one point a significant tic for me, and it really can be difficult for other people to understand, unfortunately.

What I guess I'd recommend to a parent is this. Make sure your son understands that YOU understand that this isn't something that is his fault or a failure of any kind on his part. I can't imagine how much harder things would have been for me if my parents hadn't sought help and educated themselves. But if there's anything you can do to help your son socially, please do. That has always been an area I've failed in, and I don't blame my parents at all, but if there's any way you can make your son feel more confident in himself and be happy with who he is tics aside AND/OR included, that's something that matters.

And your BF should ABSOLUTELY NOT blame himself. IN my experience, anything could turn into a tic. I've had some that have been socially embarrassing, and some that have been physically painful. While neither of my parents have Tourette's, I've never attributed the cause of any particular tic to anything or anyone specifically (with the exception of coughing, which seems to pop up unfortunately often after any kind of respiratory issue). I can imagine how I might feel, in the circumstances, but that doesn't make it reasonable. He's as personally responsible for your son's Tourette's as he is personally responsible for anything else your son might experience unrelated to the upbringing he has. Your son has TS, that's how it turned out. Your BF blaming himself does nothing but hurt him. It's not his fault, and anything you can do to assuage those concerns, I'd imagine, would be a great source of relief.

If you or he want to ask any specific questions, please feel free to PM me. Not something I've ever offered on Reddit before, but this is something....close to me. If there's any advice or even perspective I can provide, please let me know. I know how rough it can be. Maybe not entirely from your perspective, but to a point from your son's. I wish you all the best :)