How do you motivate yourself to exercise?

I’m a 33F and have always been naturally thin. I eat a healthy, mostly plant-based diet with the occasional scoop of ice cream for dessert. Every doctor says I’m fine, every weight chart says I’m fine, my clothes feel fine.

But I’m soooo weak. Like seriously, it’s gotten to the point where my partner is concerned, just normal stuff is heavy to me, like a crate of empty beer bottles or my backpack with a laptop and my bike battery in it. I can’t do a push-up from my knees, I even find myself supporting my body when I bend over to unload the dishwasher. I absolutely blame my work from home job. 3 tears of sitting behind a desk for 10 hours a day has clearly made me atrophy like crazy.

I know it’s a problem, I don’t like it. And yet, I absolutely cannot motivate myself to do anything about it. I loathe exercise. It puts me in such a bad mood, it feels like such a waste of time and I hate spending time every day being confronted with how weak I’ve become. It feels like torture. I’ve tried all kinds of things — weights, RingFit, yoga, calisthenics, gymnastics, ballet classes, rock climbing — I can’t figure out how to make it fun.

How do you motivate yourself?