>>123648192 years ago I underwent something similar, but mostly caused by all the pressure I was getting from university classes and the low amounts of sleep I was getting. Before that, I used to be able to masturbate to my own sexual fantasies (which often included lolis), and also used to be able to be aroused by "weird" stuff like yuri, futas, and traps, these days I can't really get off anything other than asses or navels.
I also tried getting into feet and armpits for a while because of then ongoing spam campaigns related to them, but I ended up going so deeply into idealizing perfect feet and perfect armpits that I can't stand looking at anything that does not correspond to my ideal of them.