guy help,,??

Okay so i was really good friends with my crush last year and we like talked all the time and this yesr he sorta started of quiet but after a while he began to talk to me and we walked to class together but then he got a phone, and he started playing this game and now he wont get off of it. Hes always on his phone and he wont talk to me. He keeps leaving way too early for me to catch up with him to walk to class, although i try to catch up and i really try to make a conversation but i cant! and yesterday he was with his group of friends for the volleyball circle which i was pretty chill with but then he changed groups to with all the pretty athletic girls in my grade and he was the only guy there and i was really hurt. My cousin told me to stop trying, and when i stop trying he might see something is wrong. Idk. What do you guys think