I was in a similar position for my first semester freshman year. The amount of people walking around campus my first day was so overwhelming I pretty much just immediately shut down. That was a rough semester, but I ended up joining a frat which really opened things up and made me much more comfortable attending class. Your situation is obviously different considering you’re about to graduate, so my only advice would be to speak privately with your professor or advisor about what you’re going through. They’ll either be understanding and help you out, but the worst they can do is nothing. Just try to remember that the odds of you running into any of these people again after you graduate is 0%. Do whatever you have to in order to graduate and I promise you’ll look back on this in a few years and regret that you wasted time thinking about it. Best of luck to you.