JMO but I would imagine that when we are physically unwell we arent as mentally prepared to challenge our anxieties, sort of like we are already exhausted with fighting the illness w/out having to be alert for obsessions and challenge our anxieties/compulsions.
I also find that when I'm rly stressed out, I'm more prone to colds. Just more evidence IMO that our mind and bodies are inextricably linked.

Feel better soon

*Willow*