Random anxiety and depression now, please help!

I don't even know where to start, but for the past few weeks I've been getting progressively worse anxiety and depression because of my sexuality. It hits me at random moments in the day and then late at night and kills whatever I'm doing. My grades are dropping and I'm losing a lot of passion for my work.

I suppose it's triggered by a large combination of factors. The first is that I planned to come out this year, but recent events both local and national have made me feel uncomfortable and panicked. My school has had to crack down on bullying because there is a sudden outburst of racism and homophobia. I thought that my school was open minded, but I was clearly mistaken.

The second thing is that I've simply been closeted for too long and my parents are insisting that I stay in the closet so I don't offend any of my family members. This alone infuriates me, and it's also contributing to my social anxiety when I have to lie about my sexuality to my family and friends just so nobody finds out. My grandparents are constantly telling me that gay people do not deserve equal rights and that it's an illness. If I ask them to stop then they literally pitch a fit and complain to my parents who then berate me.

And of course, I missed the opportunity to ask my crush out because my parents won't allow me to come out to anyone. Before I knew it he got a girlfriend (He's pan) and now I have to watch as they do everything together. Obviously there's plenty more opportunities in the future, but right now he is the only guy I've come close to asking out and it was wrenched away from me because of homophobes controlling my life. Thinking about it just makes me want to cry, and I nearly have in the middle of my classes.

I don't know how to deal with this depression, it's spontaneous and devastating. I've tried doing a number of different activities to ease my mind, but nothing is working. I have to fix it soon because it's ruining my life...