I [36-40F] found out about my husband's 3-year affair with co-worker; I worry about how daughter [13F] will be affected; we're American expats in Spain.

My husband told me yesterday he and his co-worker have had feelings for each other since August 2018.
His co-worker's 34, married with a 5-year-old son, and considers my husband his "soulmate" and claims the feeling's mutual!
We're American expats in Spain, and his co-worker's another American expat too... his employer's American.
I'm planning to divorce him, BUT we have a 13-year-old daughter to consider.
The big problem is, of course, COVID etc. making the affair an online rather than physical (although I think it's been a physical one) and I don't think my husband's ever thought of what the reality will be like, two households, two kids, two mothers-in-law, two ex-wives, four sets of grandparents, am I right?
We have lived in Spain since April 2017 and are being recalled back to the US in August 2021, yes, that includes the co-worker who's in the thirty people who are being shifted from one department to a new merged department for the employer.
I've never really had to deal with cheating etc. but same-sex cheating etc. - the same issues of bills, dirty underwear, laundry, blocked toilet, PTA meetings etc. still apply?
I'm feeling emotionally fraught and worried my marriage was a sham, even though my husband claimed "I'M ONLY ATTRACTED TO HIM, NOT OTHER GUYS!! AND MY CO-WORKER SAYS THE SAME THING!"
I don't know how to cope, not got a great support network, other than a few American expats residing here, and three Japanese couples who live here while their husbands are on assignment temporarily (for a different company, a Japanese employer) and I'm stuck in an expat bubble; the locals didn't really seem to like us as a family, for some reason (and this applies to the small American expat community here).
I'm not sure if they'll be able to help and one of the Japanese couples returns to Tokyo in three weeks time.
I want to move back to Chicago in August, although where we lived was well outside the city limits, but close enough to the center that it was like a 11-minute drive if you take Google Maps as useful.
Much as I love Spain I do miss Chicago, before we moved to Spain in 2017, we were transplants in Texas for my husband's job. My worry is how I'll fit in, as I've not lived there since November 2014 when we moved to Texas.
I can't really work due to visa issues, much as I want to, so I've had to deal with depression at times, although it's not to the level of serious depression.
I'm wondering how to cope with three big things; the affair, lookng after my daughter and getting a job post-COVID, although I don't want to take a McJob, as my background's in marketing and I'm over-qualified for McDonald's.

---

tl;dr: Husband had 3-year-long affair with co-worker, and we're being transferred back to U.S. in August 2021.


Source.