I'm sorry that you are experiencing such distress. : ( Anxiety really sucks...

Take deep breathes and listen to calming music. Cuddle with your cats (or your fiancé) and try to allow yourself to feel safe. You are going to be okay. You really are.

If you are religious, pray. Remember that your God loves you, and would not allow permanent harm to come to you. He wants you to feel better.

Eat as much as you can handle, but don't push it. I think your ice cream idea is brilliant. You are going through something really difficult and stressful; you deserve to treat yourself now and then!

If the anxiety does not improve noticeably, and/or if this has been a problem for you in the past, I would urge you to seek professional help. Soon you'll be insured; there is no reason for you to suffer...

And congratulations on the wedding!