Hello Lou01,
What to do… Dare to step out of your shell, dare to step out of your reserve, dare to talk to others about your discomfort regarding the difficulty you feel in fitting in with the group.
No one in the world has the same character, yet everyone still tries to get along with others.
Believe in yourself again!
Telling them that you have a good friend with you is not the solution, because doing so makes it seem like you feel protected by that friend rather than by the group.
Seek out dialogue with others, integrate yourself into their activities; in short, don't stay in the background—assert yourself by getting involved in what they're doing!
Have a good day
The magician.