Why is he distracting himself from me?

Hi

This guy and I have been friends for 3 years now and we were very very close, we always had long meaningful conversations and just really good friends extremely close

8 months ago we decided to... have s#x one night, we both were really close had an amazing understanding of each other so we both agreed

After that on my side everything was great nothing changed but he started getting weird... when we hung out no conversations from him, he would completely distract himself on his phone, when coming over he would always bring a friend with him he couldn't be alone with me... I would always catch him staring at me but I can't ask him because we hardly talk

It's just sad because nothing changed for me I still look at him as the same great person but for him something changed... he knows I'm still the same but he won't talk about what's going on with him

Please help

Why is he distracting himself from me?
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