May, I had a little girl that had one heat after another and it turned out that she had a cyst, I think on her ovary, that was keeping her in heat. It's been so long that I can't remember.
Anyway, my vet had no choice but to spay her while she was in heat and she did just fine. The reason they don't like to do it is because the cat can hemorrhage. I had to sign a paper stating that I wouldn't hold them responsible if anything went wrong, because I was the one who pushed to have her spayed. The poor girl was suffering for about 3 months and was driving me crazy. They even prescribed a tranquilizer to give her at night so I could get some sleep and she could get some rest also.

I pray that the first chance they get, your vet will be able to spay Creamsicle in between her heats.

Prayers and positive thoughts on the way for your precious girl and {{{{{{HUGS}}}}}} for you.