How do I stop turning red when I'm around my boyfriend?

whenever I'm with my boyfriend my neck and chest get really red, and blotchy, sometimes spreadiing to my face. I can feel myself getting super warm and I hate it. I'm not shy or embarrassed around him, so I don't know why I turn red. it wouldn't be so bad because I wouldn't notice it, but my friends ALWAYS have to point it out and that just makes it worse. I have tried the "inhale through nose, exhale through mouth slowly" technique but it hasn't worked. I have told my friends to stop saying it out loud but they probably still do. I have been dating him for over 2 months, and I'm completely normal around him but for some reason still turn red and warm
How do I stop turning red when I'm around my boyfriend?
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