This might be a bit difficult to explain/understand so bear with me.
I have this internet friend. They live in a different country so we have never met face to face; however we have been talking pretty much all day everyday since October 2019 (we talked before then but do way near as often due to my mental health at the time.) We have talked about all sorts of stuff, from silly jokes to deeply personal things, and they are by far and away the closest friend I have ever had in my life. They are also currently my only friend.
To understand things properly I should explain that I have a LONG history of being brushed aside when it comes to former friends and acquaintances. I'm always the person who everyone forgets about the moment I'm no longer in the room with them, the one people make up excuses not to see or the one who people completely forget about the moment they get a romantic partner to take up their attention.
Now, until recently my internet friend (who I will refer to as A) didn't really have much of a social life or many friends to hang out with so I had them pretty much all to myself. They were really sad about not having more people in their life though and as I, naturally, hated seeing my friend upset I was just as hopeful as they were that they would find some opportunities to change that. However, now A has started hanging out with people more and I am feeling VERY jealous.
It's actually gotten to the point where I get jealous hearing about people they have spent time with in the past (romantic partners and friends from YEARS ago who they no longer have contact with) so obviously something has to be done to get this on check.
I know that it is stupid, irrational and mean of me to feel this way. After all, friendship isn't exclusive so I can hardly expect them to not hang out with anyone, especially seeing as A and I could never actually hang out together. It would be unfair and cruel. Needless to say I haven't mentioned my feelings to A. They are prone to depression as it is and this is a rare moment of happiness for them. I don't want to bring them down with my own stupid selfishness.
However, I don't know how to deal with my jealousy and make it go away. It's not an emotion I have much experience with. Does anyone have any advice?
(Thanks in advance.)