Talking to strange girls
The big deal is that you don’t know her and she might reject you. She might do so in a mocking manner, or worse, with pity, thus causing you to hateyourself even more than you already do. The memory of this rejection will haunt you for weeks, her face, that expression of amused loathing along with a dullness that you had not seen before (or you would not have bothered). You will regret doing it. You are more afraid of the regret than of the rejection because regret means that you made a mistake, you mistimed it, misread her, was delusional, in denial. You still might be without knowing it.
Talking to strange girl is a reflection of all your failings as a heterosexual man. It is you looking at yourself, your desirability, through a woman’s eyes, the only ones that matter, and seeing where you fall short. You get to see that what you think you are may be just a figment of your imagination.
You get used to it the way you get used to looking at yourself in a mirror even after you realize how unattractive you are. You do it because the alternatives to that mirror are unworkable (shaving by touch is difficult and stressful). Do it enough, though, and eventually what you see in their rejection does not really matter. It loses its sting. If that one does not like you, you move on. You continue the search for the one who will see you the way you want to see you.