choosing thoughts and feelings

I still can’t get my head around choosing a feeling. It’s really that simple? So people who are more grounded and feel good, are just choosing the thoughts and feelings they want to have? It makes sense, but it just seems like cheating. And forced. Can you explain it in a way that makes it feel less shallow and superficial? For lack of nicer words, it just seems so surface to me. So when I’m jealous or angry, I’m actually choosing to feel those things? Do I need to dig into why I do that? I’m still not convinced that i shouldn’t choose anger or jealousy. The reason I shouldn’t is because it doesn’t feel good and doesn’t get me anywhere I want to go?

I have to understand this from an academic mindset or else it doesn’t really resonate into my brain. I want to believe these things, but I still get some pleasure out of feeling jealousy, anger, resentment, etc.