Do I have a right to be upset?

imo • 16, dancer, uk🇬🇧

So my best friend has just recently gotten into a relationship with a guy that lives hundreds of miles away, and I’m friends with him too and we’ve met him once already and we’ll see him again this week. We knew one of his mates who used to go to our school which is how we got to know him and then she was talking to him online for a good few months, and it’s been official for about a week, so it’s pretty new. And they are pretty cute together if I’ll be honest :) So the problem is that on the group chat with me, my best friend, the guy and our other friend, they don’t really have any boundaries and I can’t help but feel uncomfortable when they talk about sex and things in front of my and our friend. I’m fine with teasing and making jokes about it, I join in with that, it’s just the details that are tooo far and I don’t know how to deal with it. For example, he will say things like “I’m going to fuck you till you’re numb”, “shush or I’ll make you beg and cry for more when I see you”, “you’re going to be spent when I’m done with you” etc etc. DISCLAIMER ik this shit sounds weird but he’s not a psycho he just has some ‘interesting’ kinks and seems to be horny all the time. He’s not like this to her all the time and they actually have a very sweet relationship. The thing is I just really would rather they kept that side of their relationship to their private messages because I don’t want to think about my best friend being choked when I’m trying to have a normal conversation you know? We’re also only 16 and I’d rather just enjoy talking to each other on the group chat and having fun in life. I’m single, although I got out of a terrible emotionally abusive relationship a few months back. My ex used to tell my friends details about our own sexual relationship without me actually knowing, which is okay I guess but there were certain things that I would have NEVER shared with my best friend (and she always uses this as a come back when I talk to her about the thing with her and her boyfriend). I feel like certain things should just be kept to a couple and not shared, even with close friends. Do you guys agree? I just really don’t know what to say to her at this point.