Not receiving calendar invitations from an iCloud calendar user

Hi so my Apple ID is name@example.com (I have a domain email as my Apple ID) and my friend has an email as friend@gmail.com (actually a gmail) that he uses as his Apple ID. He doesn't use google calendar but rather sends invites for calendar using icloud calendars. Every time he sends me an invitation I don't get them.

i use to think it was an issue with my email provider then thought it was with my domain but now I realize it has to do with the fact my domain email is also my Apple ID. I deduced this because the moment I enabled my iCloud calendar all his invitations appeared on that calendar in particular.

Does apple when using iCloud calendar seem to send invitations to Apple ID emails and not the email itself? In other words is it true that apple ids are prioritized over sending the invitations through via an actual email? It seems the only real way to solve this is to change my Apple ID to some other email to make sure my Apple ID doesn't match the email I want to use to receive invitations from other iCloud calendar users.

keep in mind my email works with every other calendar invitations this is only happening with iCloud invitations from iCloud calendars specifically.