Hi JG and welcome back!
Although I am sorry to hear it is due to returning challenges. I tend to not deal with depression often, as anxiety is my primary issue...but sure, I think we can all related to having anxiety and or depression come out of seemingly nowhere.
However, even if we don't know the source/cause of our unwanted mood(s) that doesn't\'t mean we are powerless against them!
You mention having a therapist...so perhaps you can ask him/her for some increased time/sessions to get you through this rough patch...
...or maybe just some homework in the form of exercises/therapy worksheets. If theses are not options, you can always do some self help by getting a new CBT workbook....or even just revisiting our Resources for material.
As far as missing having a pet...I completely understand...as animals bring so much joy and comfort to our lives! Until you can have them in your house again...is volunteering at an animal shelter an option that you could consider. Having contact and helping animals in need is therapeutic...even if it just for a couple of hours a week.
Wishing you much progress. Keep posting with us so that we can keep you in support!
S.C.