How do you cope with feeling incredibly unattractive

As the title suggests really...

I'm at the point where i avoid relationships with people because im afraid of how they turn out, how i am in the relationship... every now and then i think i should try, you know, when i get lonely... then if i get rejected or ghosted or w/e it just shatters me

The only way i can have physical contact with women is if i shut myself off completely, but then im just completely emotionless and they end up wanting more than im willing to offer

I also don't know how to tell people... on the one hand i want to be up front and give people the opportunity to run away and avoid the turmoil, on the other hand i dont want the disorder to ruin every relationship even before it starts... What a mess