No science to it at all wear whatever you want.
At the height of my stuffing days it was a loose top and yoga pants.
There were times I wore shorter tops so my belly would would hang out.

No regrets.
Beats being skinny any day.

18 is really young so don't worry about being alone.

I was on feabie the first week it was up and running.
Stayed for a month or two and the hate and discontent was awful so I left.
You make a post and people would pile on you and cuss you out and call you everything under the sun.
It was too much like a high school clique.

Yeah I have done that a few times

Its amazing for someone to be in a relationship and not care what their partner wants and willing to use them for their own fantasy.

You are a complete jackass to do that to her.
Just ask her and see what she says to the idea.
A real man would ask because he isn't afraid of his girl friend

I like both on a female and a slightly plump one on a guy.
Its funny how its so different for everybody.
I had a thinner face when I was 400+ than I do now at 340.
Not sure why but my face has plumped up a lot and I have a double chin now.

I think you are overthinking all of this.
If you find a guy you like and then get to know him you may forget all about your fears because you will see they are just fantasies you have.
Don't let your fears take over your life just let things happen naturally.
Like you said you have never been in a relationship so you really don't have any experience in the matter so you don't really know what is going to happen.

Wow sounds like you are in for a ride.
better buy some bigger clothes now because you are going to need them.