I don't believe a friend's reason for dropping me on Instagram
Is there a reason that you need to know why he dropped you?
Not really, but I just don't want to give him another chance.
You seem pretty mad to lose him on Instagram, but it's wrong not to believe your friends. Maybe you could talk to him about whether something else is going on with your friendship.
I feel like I don't need to talk to him, I will block him though. I'm better of without him anyways.
If that's how you feel then you should. Friends come and go anyway.