I think it’s perfectly fine to look up persons credentials and go on their professional website. I think looking up their professional FB page is fine too. Looking up if they are married is fine too as it’s important. But I’d refrain from going on guy’s wife’s Facebook page. She isn’t your therapist so I’d avoid that.

Also if you really don’t want to get attached, maybe staying off his personal life like his wife’s page could help you to not develop too much of attachment. Just a thought