Nothing to forgive, but when I'm unsure of a gender I try to determine it by how masculine or femanine the name sounds and if all else fails I'll use they/them/their/they're or their name outright, etc. But you're right, the English language can be bulky and a pain in the arse... so many rules, so many exceptions to rules, so many unique distinctions... *sighs*
Maranwe
P.S. Yes, I realize my alias name can be difficult to figure out my gender from