I don't know if it's due to my autism or the social anxiety that comes with it but I feel like I don't belong in any friend groups I have, I feel like I'm that unimportant side friend that no-one will miss that exists on the outside of every group. I even feel this way when I introduce friends together to form a friendship group, they always become good friends, more people join and I end up getting pushed to the side or kicked out of the groups. They stop inviting/involving me to things and stop talking/replying to me.
It just keeps happening again and again, even the furry fandom has given me the same feeling. I don't know what I'm doing wrong. I don't know why I feel so lonely.