You need to be logged out of to start recovery process.

https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=3456188107

What counts as viable proof of ownership:
https://help.steampowered.com/en/faqs/view/40A0-8B4B-B54B-C51A

Steam dropped around that time yesterday, a lot of users getting re-log messages within STEAM client itself. My strong suspicion is that this was an internal breach they will never admit to.

If you were prompted by STEAM to re-log around that time yesterday and you entered your profile information I highly suggest you replace your passwords from a clean terminal.

Your "boyfriend" was not hacked, they were PHISHED. Tell your "boyfriend" to stop visiting shady websites and downloading shady software. They likely entered their details on an obvious phishing website.

See the guide below for help.

https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=3456188107

Originally posted by PotatoBasket:

Weekly maintenance. Happens all the time. Not a security breach.

The OP lost access to their account(s) because their visiting shady sites, which is the norm.

a lot of users getting re-log messages within STEAM client itself.

Looking through the forums for the past 24 hours, there isn't a single post complaining about such. If such an event happened, the forums would be flooded with complaints.