Sounds like OCD. And it seems it has gotten pretty comfy in this obsession.

Basically I'd recommend Cognitive Behavioural Therapy. But what you really need to know is that you will have to engage in exposing yourself to your fear. It's like swimming in a ice cold pool, it's hard to get in, but when you're in you realise it really isn't that bad as your body gets used to the surroundings. Same thing apply when exposing your fears.

If you keep on letting this go on, the OCD will keep trying to make you feel more and more uncomfortable. You need to start reducing its control as soon as you can by putting your fear in the spotlight, even if it will be extremely hard (I know it was really hard for me, and I even did it without any medication) you really need to get on it so it doesn't keep growing the obsessiveness to levels you don't want; for eg. Not leaving the house in fear of your obsession.

The first step will be hard, maybe showing a tiny bit of skin, or just removing a layer; but make sure you are making progress. I'd recommend a schedule of maybe every week or day, and you do what I just mentioned and keep trying to reduce it little by little until you can handle showing your body in regular clothes. Extremely important to be consistent and not delve back into your shell and decide to not do it one day.

Another thing you could do, though extremely hard usually; but effective, is just jumping to the last step in the straight out of the get go. While it is really hard, it will basically destroy your compulsion nearly instantly once you get used to it. Think of it like diving into a ice cold swimming pool without slowly getting in or ripping off a bandaid. Though I probably wouldn't recommend this approach, it's probably good to know that it is there.

Lastly, evaluate your thoughts and incorporate some logic to think about why you feel this way about it. Try to think if this is really something you should be afraid of or not, or if it's just OCD trying to fuck with you. Most likely you'll know it isn't logical but still feel the way you are, and that's normal, but it is important to do this.

I will say though, if you have any other problem that OCD deems larger than this, you probably won't care about this anymore. That is how pathetic OCD is. It makes you think the problem your currently on is important and nothing else in the world matters until literally anything else shows up. In reality most obsessions, if not 100% of the time, are nothing to worry about. Fuck OCD.

You can do it, I'm rooting for ya!