The document you received--it isn't a subpoena is it? In other words, you do not have to appear, and if you do appear and feel uncomfortable, you are free to get up and walk out at any time.

Perhaps go speak with them---or better yet LISTEN to them. Don't feel pressured to sign anything or feel bullied. If you are asking to sign something, decline, take time to think, take documents with you and don't feel imtimidated. I also would not go alone. Take a friend, or family member with you who can offer you support, balance, and direction.

Good luck. It may not be as bad as you think---they may be willing to work with you outside of the debt agency in resolving this debt.