I recently left a job, and one of the reasons I left was because I felt like I didn't belong there. It was a very social company and I would hate attending the office as every week it seems like there was a social, or happy hour or team lunch and I just felt it all too much.
I dreaded leaving because I felt like I wasn't liked by my colleagues, or at best that they were completely indifferent to me and it would be embarrassing as when people leave they have a meeting and are given a card and gift. I had visions of nobody attending the meeting, or my manager awkwardly handing me a card nobody had signed or trying to awkwardly explain that no one had put money in my collection for a gift.
It was the opposite. Lots of people attended my leaving meeting, and signed my card and I received a generous gift. I had colleagues messaging me on my last day with really kind words, saying I'm easy to work with, lovely, helpful, a valued member of the team, etc. I was really taken aback by it all as I wasn't expecting it at all, I thought I was annoyingly quiet and boring