I'm a naturally shy person who has to force myself to be sociable in new situations, especially around new people. I know *exactly* what you mean when you describe the awkwardness you can feel sometimes, and feel like I could have written your post myself at some point in the past.
I say all that to point out that I think you know that this has more to do with you and much less to do with them. And, to say that this is such an amazing opportunity for you!! It took me more years than I would like to be able to fake my way through a meet and greet, and I think this is a great way for you to learn in less time what it took me years to learn.
When I say "fake my way through" I don't mean that I'm acting fake or that I'm being insincere. I mean that I have to convince myself that I'm likeable, and that no one else sees the awkwardness that I see in myself. The more I think about myself, the more I draw in, get quiet, and stop meeting people. The less I think about myself and the more I remember to fake my confidence, the easier it is to step outside my comfort area, talk to people I don't know, and just enjoy myself. I've actually had people tell me that their first impression of me is that I'm really outgoing, which is crazy talk! In my mind, I'm the least outgoing person I know. But I can fake it pretty well, apparently.
I'm not saying it's easy, but it is a necessary skill that will serve you well when you start working. I can't tell you how many networking events, training sessions, and cocktail parties I've had to go to for work, and this is a skill you will use for all of them.
Bottom line, my advice is to stick it out, and use this as an opportunity to train yourself how to be more comfortable in situations where you are surrounded by a large group of strangers. If you can convince yourself that you'll have fun, chances are that you will. If you feel awkward and want to leave, make a promise to yourself that you'll stay 10 more minutes, and if you are still miserable you can leave then, but at least you will have stuck it out a bit longer and who knows what will happen?
Good luck!! I think you'll be great.