I just left my job at a very friendly and open office. There were lots of people in my age range (mid-late 20s) and we were generally a very close bunch. We all chatted daily, went for coffee/lunch together often, and had regular after-work drinks.
One guy who I occasionally worked with seemed very shy, and didn't have much to do with the rest of us. I made a couple of attempts to chat with him during downtime, and once invited him out with us after work. He wasn't very responsive, so I stopped bothering. A couple of other people in the office had expressed that they found him hard to talk to as well. In my last couple of weeks I only spoke to him for purely work-related reasons.
Fast forward to my last day. I was going around the office saying goodbye to everyone before leaving, and he saw me approaching. He started getting ready to leave extremely quickly, and basically ran out of the door before I could get to his section. I wasn't planning to say anything to him anyway, but it really caught me off guard.
I'm left wondering how I could have possibly made him feel this uncomfortable. Everyone else was lovely to me - I received cards, presents, and many heartfelt goodbyes. But his reaction really put a damper on my final moments at work and has made me worry about myself. Whether I somehow came across as creepy, overbearing, etc in his eyes. AIBU to take it personally and feel upset?
Tl;dr - A coworker who I had tried and failed to be friendly with avoided interacting with me on my last day at work. I can't stop worrying about why this happened and feeling awful. Not sure what to think.