Man in 40's here, i'll give my perspective.
During early covid, me and two mates were catching up on zoom calls and reminicing about our great European adventures of our 20's/30's (Prague, Berlin, Barcelona, Milan etc.) as a trio.
We resolved when things blew over to live a little and head to Amsterdam for a long weekend. We had a great time, but the great time 3 happily married with kids, slightly out of shape professional men have. Visits to galleries, sightseeing, less clubbing, more nice meal with a good bottle of red.
Whilst it was a lovely break it did rather underline the fact that the first flush of youth has departed and we are now 3 middle aged fellas - not that there is anything wrong with that - we are doing Bratislava later in the year!
I'm guessing that the OPs husband might just have gone and made a dick of himself chatting up some girl with whom he exchanged numbers, and once sober she blocked him, and he's realised his youth has departed!
But he should have got over that in around 20 minutes, and got back on with his life and counted his blessings.
If nothing happened, and he's slipped into a depression, he needs help.