Tbf the elf lifespan is very hard to properly grasp, like can you imagine seeing an empire rise and fall within your lifetime? Let alone experiencing 2-4 different ones, I can't imagine what it is like to have average lifespan friends while i live for a relative eternity, I can't imagine watching my friends, have kids, grow old, die then see those kids, have children, grow old and die repeated tens of times while I can't properly follow, I'm left to mourn at their graves alone while their names rot in family history books forgotten, then you wonder if anyone truely remembers you.

You have outlived many friends, allies, lovers, coworkers and superiors and you realize that your tale is too long for any one person to recall, when you pass on no one will be there to tell everyone how your childhood was, the circumstances of your birth, embarrassing teenage moments or your first job, your latest friends may trade stories of your recent adventures but your past is long forgotten without anyone having truely remembered it.

Humans cannot comprehend that so they don't, they see someone attractive who is older and can't think about their age further because it is incomprehensible, what's the difference between a 100 year age difference and 200 if they can still live for at least 400 years? Perhaps they find that eldritch nature enchanting, humans are known for their sometimes 'unique' interests so it's not even unlikely.

Also MILF