How can I find happiness?

Honestly lately, I haven't been the happiest person in the world. My friends stopped talking to me, so did a lot of my new friends too. And whats worse is that I tried to go on a forgiveness binge and one of the people I hurt said:

"Natalie, to be honest, Fuck off, I have a perfect life without you and all you are to me is just a burden. I have a good job and a girlfriend who's faithful. And I don't need someone to weigh me down. So do the favor and stay out of my life." In my face.

And honestly I have never felt so shitty in my life. I'm also doing a job that I hate and I'm doing classes (electives) that I hate

Everyone in those classes judge me for how I work.

Its gotten so bad that I've considered dropping out of school. How can I find happiness again, if I've been rejected by so many people and criticized by all of my classmates in my electives?

And will I find happiness? Because at this point it seems hopeless for me.

And because I have BPD Borderline personality disorder, its hard for me to accept all of this.