You asked for a male perspective OP, so here's what I'll say, as a male.
This is at once better and worse than if he'd actually cheated on you.
Better: He's fallen in love with a fantasy, an idea, a dream, which was never going to become real - it couldn't have, she's a webcam model, not someone he has any prospect of having a real relationship with. He sounds like a sad case who needed his ego boosted by being told how nice he was by some young one, but if that's what it was, just an ego boost and a fantasy, then it can be fixed. More like interactive porn than an affair.
Worse: He's an idiot. These women are professionals at finding fools to spend money on them , knowing that they will never ask for anything in return. He's thrown €3k of your money (a lot) away on some woman in the US who's been laughing at his pathetic need to pay her and buy her things even though she'll never meet him or know anything about him - or care for that matter. He could have logged onto any number of websites and gotten his jollies for free.
I don't know. As a man, I think this is probably the most pathetic thing you can do. Not the WORST thing you can do - actually using prostitutes and actually having affairs are worse, IMO, but this is definitely the most pathetic thing you could do.
If you love him, you love him. If you can get over it, good for you. But if I were a woman and married to him, I'd boot his candy ass out the door and tell him to ask his fancy woman in America to take him in. She won't want to know him.