Affair nearly destroyed my marriage! How do I [51/f] deal with the 'other woman' [58/f], when I next see her?

I discovered earlier on this year that my husband (m55) was having an affair with what I thought was my best friend. Cutting a long story short, my husband and I are now back together after I asked him to leave for a while. We seeked professional Marriage Guidance Counselling and decided to try and rebuild our marriage. The problem is, the 3 of us went to a dance club together. When I discovered the affair, the club asked her to stay away as they were a tremendous support to me - I have a lot of good friends there. I continued to go to the club, my husband returned with me and everything seemed to be getting back on the right track. However, I have now heard 'she' is returning to the club later on this month. My heart pounds so hard and I feel sick and shakey at just the mere thought of it! How do I deal with seeing her again? I need to keep my dignity here! Any help would be most grateful. Thank you!