Yeah she defo was. I said this to my mate and he reckons she's only gonna be in one episode
She's back next week I think (episode 3). Swiped this from the Radio Times website:
"Mark is having doubts about marrying Sophie so joins a gym in order to spend time away from her, but it soon transpires that his personal trainer takes exercise extremely seriously. Jeremy discovers his ex-wife Nancy has started working at the gym so takes a job as a cleaner to try to get back with her, but his former partner takes a shine to trainer Matt."
Apologies if this is a spoiler, no idea how to mask it.