I understand you completely. When we visit the inlaws, sometimes I bring my bike and other times not. Sometimes it rains the whole time I'm there, and I also suffer from withdrawal. I go for long walks but it's not the same.
I've this whole week off from work, and the forecast is calling for 3 days of rain and then maybe more. I went to the gym and rode a spin bike for an hour and lifted weights. A poor substitute for actual riding but it will have to do.