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 
