Why can't I find a job that makes me happy

I used to study art, until I thought I wouldn't make enough money doing so. I was good at it, but I didn't want to do it. I get influenced so easily...And what did I do? I started working as a software engineer and I'm horrible at it. I can't quit now. But I'm learning really really slow...I come home everyday unsatisfied about my performance. I study, but it doesn't help me to solve my issues. I don't know what I should do. Last week I got into a huge fight with my boyfriend. I went outside at night, crying on a parkbench and reflecting my life. That I don't know how to continue and giving up seems so much easier than to keep going. That without my boyfriend my life would look a lot different, not sure if better or even worse..I've lost my passion about things I liked. I get respected by many now for working in IT instead of art. A friend of mine told me: the worlds needs people who are good at what they're doing, not what they want to be good at. And I'm not good at what I'm doing, I quit what I was good at. He said it would take him soo much longer to be good at what I'm good at while I would finish it in no time. It seems like I completely failed myself and sabotaged my future.