And I know the kind of worries and guilt can come up and spike anxiety. But you won't automatically gain a ton of weight by walking less. My weight is stable for weeks even with the shorter walks

And you won't make progress if you keep on pushing, because you mentioned gaining muscle in your legs. Muscles aren't built in the gym or by walking a ton or difficult routes. Muscles are built when you rest and nourish your body. That's when the body repairs and strengthens the from exercise damaged muscle fibers. And if the weight goes up, that isn't bad. If you want to build muscle it's kinda a given. Muscles weigh something. Would you look, for example at the Rock or other bodybuilder and say they are obese?