I really think that you need to face this head on, no matter how hard that seems.
Go to the meeting.
Explain that you seem to be having some communications issues with some of your colleagues and despite your attempts at being friendly and polite, you don't feel very included at work.
This has led you to find the current atmosphere in the office very difficult to cope with. You're uncertain of how to resolve the problem on your own.
Explain that you really want to be back at work and would really welcome their suggestions on how things could be improved.
Try not to be emotive (though v. difficult I guess).
If I was your employer I would not want to be hearing about sweetie sharing etc. And from that point of view, asking to be moved to another job because you can't cope with a couple of petty girls would give a very bad message.
I realise you have had your confidence knocked for six, but you ARE an adult. You need to take a deep breath and get this sorted out. By running away from the problem, you are ENABLING the behaviour of the others. You need to tell yourself that they are not worth worrying over and get back to work head held high.
It will be hard, I'm sure of it, but you are BETTER than them. If it was me, I would go to them at the coffee machine, and say something direct to them along the lines of "I'm very curious about the way you are behaving towards me, have I upset you in some way?"