How can i tell if my crush is jealous? and how do i make it better?

me and my crush always talked and flirted he knows i like him and he never asked me out for over 3 months and i gave up bc i didn't want to be just a toy. and i have a boyfriend now and my crush[still] has stopped texting me and when i talk to him he wont even look me in the eyes. we ride the same buss and i was sitting with my guy friend that my crush isn't friends with. so when my friend got on the bus my crush kept looking at him, and i was laughing and smiling at my friend bc well we were just talking my crush gets off first. so he walked by the door to get off and his head was turned sideways and i don't know but i got the feeling he was looking at me from the corner of his eye. idk just the feeling. and he doesn't really wanna talk to me no more,