Would you be worried about this guy? Real advice please.?

Long story short - my sister lives overseas, we communicate once every 2-3 months, very seldom. Anyway, about 2 years ago she claimed she started seeing this man and their relationship got pretty serious, she said he is a famous director for celebrities from where she lives, supposedly he works with a lot of big... show more Long story short - my sister lives overseas, we communicate once every 2-3 months, very seldom.
Anyway, about 2 years ago she claimed she started seeing this man and their relationship got pretty serious, she said he is a famous director for celebrities from where she lives, supposedly he works with a lot of big names etc etc and that he is always busy.

It's coming close to 3 years now, she continues to tell us she is super happy in this relationship, theyre supposed to get married end of this year (tho there's no engagement ring, they dont live together). Whenever I ask for more details she tends to dance around the subject and avoids my questions. I asked her to send me a picture of him, she ignored my question.

No one has ever met this guy, not even the extended family members who live close by her. My parents went to visit her last year, my folks flew for 18 hours, stayed at her place for 2 weeks and there was not a single sign of this "bf". He never came out to meet my parents, never called to say hello, my mother said there wasnt even a single picture of him or of them taken together! My sister got defensive and said he's a "really busy man" and very "famous" and spends a lot of time working bla bla bla.
The last time my mother and I confronted her about this seemingly non-existent person, she got defensive and stopped replying to our emails and calls. We havent heard from her since.

Would you be worried? Is this type of relationship possible, could someone actually be this busy? Is it reasonable to suspect my sister might be suffering from a mental disorder and that this person is purely fictional? Or am I just being "non-supportive" as she is currently accusing me of being? Should I just leave it alone?
thanks in advance, serious response only.
Update: Jada: It's interesting you said the "edward cullen" thing because that's exactly what my mother thinks, the guy might exist but the "relationship" itself is fictional. She's acting like a stalker or a crazy fan of some sort. Sad thing is my sis is pushing 40, not a kid. Thanks for everyone's response. I guess... show more Jada: It's interesting you said the "edward cullen" thing because that's exactly what my mother thinks, the guy might exist but the "relationship" itself is fictional. She's acting like a stalker or a crazy fan of some sort.
Sad thing is my sis is pushing 40, not a kid.
Thanks for everyone's response. I guess the best thing to do is to leave it alone.
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