Most triggers are just in my head?

I've noticed, especially lately, that a majority of the things that cause my anxiety to flare up (which seems to happen almost constantly) is just when I'm thinking about things. I'm not really around people all that often outside of work, so I'm pretty much just left to myself 24/7, and I'm honestly getting pretty tired of myself. I'm constantly thinking about all of the problems in my life, even if I'm not actively thinking "this is a problem."

For example, I want to lose weight/get stronger/be healthier but I can't seem to push myself to do it on my own, so I really want to go to a gym and start eating better foods. Normally, people would think "oh this is super positive, good job Bailey," but then I immediately start thinking about my money issues and what would happen if I were suddenly without a vehicle (I don't have a working vehicle that is necessarily "mine"--i'm just borrowing a car at the moment). But then I continue to imagine what it would be like if I were able to go to the gym 2-3 times a week and what'd it be like to lose the weight like I see so many other people doing, and it just gives me so much anxiety because I'm about 90% positive that it won't happen, or at least won't happen like I think it will.

And that's just ONE example of something I think about constantly. I have so many other issues I don't know how to deal with, or I deal with very poorly. I feel like I'm just driving myself crazy and it's really been taking a toll on the few relationships that I consistently have, especially with my boyfriend.

What do you do when a majority of your triggers are in your own mind? When you feel like your own worst enemy? It's not like I can just step away from myself...