How I’m secretly in love with my best friends brother

I F16 and he is m15 my friend is f16 so me and her have been friends for about 5 years, me and her have had our issues over the years because she never listened to my boundaries so i became slightly closer with her brother and this school year, me and him became very close.

I believe he liked me last year and so did i but unfortunately i had to stay away because his sister was always mentioning how she doesn’t like when friends date siblings so I listen and forced myself to drift away. Until recently my friend told me she thought he was cute (I didn’t like him at this point and no one knew that i did before) and my other friend gave her his snap and since i became very close with him again and i set up hang outs for all of us. They talked for about a month and then he was ready to ask her out and she said she wasn’t ready and then on Halloween she was being very weird towards him and like “rejecting” his hugs like a lot. So after a week she told him she just wanted to be friends and not be a talking stage anymore.

It’s been about a month i believe and one of our friends liked him while he liked my friend. (Sorry I’m trying to avoid using peoples names) so once they stopped talking the girl who is friends with me and him started being weird towards me bc she thought i liked him which i did but I didn’t act flirty with him at all nor did she say she liked him but after him and my friend stopped talking she told him she liked him, and he rejected our friend.

There is a trio between me,him and our other guy friend. So we basically ft everyday and i hang out with my bsf and him a lot and so once he stopped talking to my friend he asked me if i wanted these 3 stuffed animals because he knows im obsessed with batman and one was about batman and the other 2 were ninjas turtles that im obsessed with the as well. He has also recently given me a batman Arkham knight game, lego batman, lego ghostbusters, and ghostbusters game.

I always feel like he is flirting with me there are so many scenarios and the way he looks at me makes me flustered. People always have asked if me and him are a thing (i mean that happens a lot when girls are friends with guys) but like the way he looks at me might just be because he has brown eyes. Plus I’ve asked his sister if she thinks he likes me but she said nooo he is always like that, i thought the same but idk i just had hope.

I just i realized that i really do like him and i wish i could have him but i can’t because my bsf/his sister doesn’t like when friends date siblings and he was in a talking stage only a month ago with my friend and im not like that i can’t go for someone after my friend just liked them, and my other friend liked him so i just am gonna try to stay away from him and not talk as much unless he reaches out because i can’t do this anymore. I want to be with him so bad that it hurts