Do Aquarius guys deny when they like a girl?

So i've had a crush on this guy for 2 years and he used to be really sweet and flirty, always talk to me first. etc. then all of the sudden he just started acting mean and stopped talking to me. He started talking meanly about me to people. BUT... he stares at me like EVERYDAY. i see it and my friends see it too. One time my friend told me he saw my crush staring at me and my crush's friends were talking to my crush and he just nodded with his mouth slighty open staring at me and saying "uh huh." But one time I got my friend to ask him if he liked me (this was 10th grade year we are in 11th now.) and she said to him "Do you like her?" And he said "Yeah I do but she's kind of stalkerish." And so my friend says to him "Why do you stare at her?" And he said "I don't for real." And she has seen him staring at me so she says to him "Yes you do." and he just started smiling and looking down. Oh and I haven't done ANYTHING to make him say I'm stalkerish. I don't even talk about him. Advice? Why does he do this? Thank youu.