You pointed out that after isolation your stutter gets worse, that caught my attention as I notice the same thing with myself and it truly is a vicious cycle. My advice may sound cliche but it works with me. Just put yourself out there and it will improve slowly with time (for me at least in a few days up to a couple of weeks). The more you talk the easier it gets, that’s what I noticed on myself. For example, after each vacation, my stutter takes a hit and gets worse but when I get back to work and am forced to speak a lot and have to go to meetings and present, it slowly gets easier day by day. I don’t know if that’s helpful but I really have that exact deterioration after isolating myself a few days.