I know rationally that people can have multiple friendships and that spending time with one friend doesn't diminish their want to spend time with me... but sometimes it's so damn upsetting when I feel like my FP (or just any friend in general) is replacing me/spending more time with someone else.

And the thing is, of course, I don't get mad at my FP! I get mad at whoever they're spending time with. I don't say anything but I seethe and split and think they're the worst.

Any advice on how to deal with this... or at least an acknowledgement that I'm not the only one that gets this way?