OK. I am very happy that you have a boyfriend. Because HE will be the answer to your questions. First, those first two situations are not stupid. If it affects you, it's not stupid.
Secondly, your boyfriend is the person you need to cling to most. You said you have weight issues. That's understandable. Im 295 pounds, lol. Granted im not a girl, (which totally changes the situation) but i atleast understand slightly.
Honestly just talk to your boyfriend. He can do things i cannot. I cant hold you and tell you that you are beautiful, and that everything will be ok....but he can. Because truth is, you are. When you said that you want to just basically be chill. You dont want mean people around you, and you dont like to argue, that shows me that you have a beautiful personality. Which is something that a vast majority of people do not have.
And you do not have to have thick skin. Many things are mental. When someone is rude to you, if you physically and mentally block it out, maybe even laugh about it, you will see a noticeable change in your attitude and mood.
Talk to you boyfriend, its a GREAT starting point. :)
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Im a front porch sittin, guitar pickin, moonshine sippin,
baccer juice spittin, COUNTRY BOY FROM THE WOODS.