Friends and family think my cousin is grooming me, and I’m starting to get worried

So to get a clearer view of my situation at the moment, I am a 31yr🔄 F who just recently moved in with my aunt. Before I had never really known my cousins living here, including my one cousin Jack (fake name for privacy reasons). Jack is a 19yr M and was adopted a few years ago, and this is one of the main factors of the whole grooming thought. Me and Jack didn’t really get close until November-December 2025, and I moved in around June of 2025. We got close pretty fast, and my sister (28yr F) wasn’t really comfortable with the way he showed affection towards me. I didn’t really see how the whole thing was weird, considering I was comfortable with it. Everytime we would hang out or even when I was just sitting around, he would sit pretty close to me. He’d put his arm around my shoulders and stuff and it never really got farther than that, until about a month ago. We would lay in his bed and pull me pretty close, to the point my head was on his chest and he would scratch my head or rub my waist, which again I never really thought much of since I just saw it as cousin bonding, but the problem is is that I’ve never really had a cousin, or rather a cousin who’s older than me and is a male (not saying gender truly matters is situations like these, but a lot of my friends brought that up as weird and off putting). One day we were sitting on the couch and his arm was around my shoulders, and my mom pulled him aside and had a private conversation with him. When he came back he sat back down and said that he can’t have his arm around my shoulders out in the living room because my mom didn’t want my other cousin to think weirdly of me or him. I wasn’t really bothered by that, so we just hung out in his room and he showed the same close affection towards me, and I gave the same to him. His room is upstairs and mine is downstairs, so we usually just hung out in his room, but we had started to hang out in his room (his suggestion) for some reason. I didn’t really think anything of it, I was sort of glad to be in my room anyway because I have a tv in my room and he doesn’t, and I was sick of scrolling on my phone. The one day we were laying in my bed, things got a little close and personal, and we were cuddling in a way I didn’t really think cousins should be. His leg was between mine, my hand was on his stomach, my head was on his chest, and I knew I knew I should’ve stopped and set boundaries, but I was scared that if I did that I would loose family like him. Me and Jack had been through a lot growing up, and I feel as if that’s how we got so close so fast, so that’s the reason why I didn’t want to loose a guy like him. We always talked about what has happened to us in the past and things like that, and he always listened intently and I’ve never had someone like that before. We laid like this for about an hour before we sat back up, his arm still around my shoulders. Whenever my mom would come out of her room or if we heard her getting up, we would sit up and space ourselves apart slightly, which I thought was odd..because why would we need to do that if this was normal cousin behaviour? I talked to my friend and my sister about it and they said it was weird and that he was grooming me and acting like a p3d0fil3, and I was a little on edge about the whole situation. There was a big fight about it when my mom came downstairs and saw us sitting together with his arm around my shoulders, calling him creepy and saying things like “cousins shouldn’t be that close together” and “you guys aren’t even blood related”. I’m starting to believe things were weird between us, and something my mom said was that she told Jack not to have his arm around my shoulder at all, which is not at all what he told me that private conversation was about. We haven’t really been that close anymore since the whole argument with my mom and my sister calling him nasty names, and he has since moved out. We still hang out a lot, and I go to his hockey games alone with him since he now has his license and a car. Sometimes when he’s driving he’ll still slide his arm behind my neck and scratches my head, and I’m scared that he doesn’t see me as a cousin and more as someone he can do anything with. I don’t feel like this at all, and I only see him as a cousin and nothing more. I feel this whole situation going on with Jack isn’t mixing well with my mental health, already having problems with that section of my life. He just recently got a girlfriend, but I feel like this odd behaviour isn’t ending, and it’s worrying me. I seriously hope having a girlfriend stops this whole thing though, but I’m not sure it will. I’m almost 100% positive going to Reddit about this problem might’ve not been the best idea, but I felt like I needed to get this off my chest. If possible, a little bit of help would be greatly appreciated, as well as a few more opinions on the whole thing. Maybe this’ll open my eyes a little more and let me see this whole thing clearly.