Needless to say, 腐女子[fujoshi] means a BL(Boys’ Love) fangirl though some people think it means a female otaku. So some female otaku might not like to be called 腐女子 unless they like BL. Anyway, there are generally some classification for 腐女子 depending upon the age.
In general, it is said that 腐女子 vaguely means from a schoolgirl to a late twenties. If she is married, she would be 既腐人[kifujin]. It puns upon 貴婦人[kifujin"noble lady"]. 既[ki] means already done, so here, it means married. We Japanese say 既婚[kikon] to describe a married person. So…既腐人 means a married 腐女子.
If she is over 30 years old, she could be 汚超腐人[ochoufujin]. 汚[o] means dirty, 超[chou] is super-…oh no, forgive me! But it also puns upon お蝶夫人[ochoufujin] who shows up in the very old anime, エースをねらえ！[Ace wo nerae!] She is well-bred, and her real name is Reika Ryuuzaki(see above image). But know this term is very rare, and I said if she is over 30…however, it’s not sure. We yet to synchronize the general definition. Speaking of rare, I hereby introduce one more term, 麻婆豆腐[mápó dòufu]. This is actually Chinese food; mincemeat and 豆腐[tofu"bean curd"] with hot sauce…something like that(see below image). As I have said, this term is very rare, so I have no idea how old 腐女子 could be entitled to be 麻婆豆腐. But I guess this might mean over late fifties because second kanji 婆[ba] means an old woman.
I yet to wait for more precise definitions coming out. I have done my best to investigate , but I have not been able to figure it out. orz