My coworker and I had working together in a small office for 6 years. We have become friends but in the beginning I explained to her that I do my do well with girl friend due to the fact they ask a lot and I was newly married and trying to have a baby.I wanted to make it clear that I was not the type to go out or hang out after work. She understood. Now years later she got engaged and asked me to be her Matron of Honor.i was so happy for her that I agreed immediately. We started working on everything and because I'm a very orderly person she asked me to handle everything the day of since I have had a wedding myself. But now that we work together and are planning this wedding our friendship has dwindle and affecting my work and I'm renting her. I'm also making some of her decorations and when we have a bite to at work I feel like she is using me for free labor. I would like to withdraw from her bridal party but how do I say this and keep our professional relationship intact?