Is life meant to be lonely?

Thankfully I have both my parents alive and a few close friends
who care about me deeply.
But someday I’ll have to leave parents and when married,
so will my close friends.
when I’m with people in general
they don’t seem to care about me at all, as if I were an invisible man. I can actually see that most people don’t care about me,
unless, after approaching several times, I take a lot of time and
put forth a lot of efforts and become their friends.

Otherwise, I feel like an extra or some kind of non player character(NPC) in a computer game who attends to their needs.
Am I being sensitive and has life been this way forever
or are there problems with me and people?