I'm jealous of my friends
Why are you jealous of your friends?
They all have girlfriends while I'm still single.
I understand what you're feeling, but it isn't productive to be envious of your friends just because they have girlfriends. You should be happy for them, and that will make you more likeable and fun to be around, which could also help you find a girlfriend.
Fuck happiness, it's overrated. I'm going to try to make my friends feel the same way I do so they can know what a horrible empty life it is.
It doesn't make sense to me that you'd want everyone else to be unhappy just because you are. Spend your time on dating apps and get your own girlfriend instead. You can do it!