We fell in love with each other and she disappeared

Excuse me in advance if my post is too long, I'll do my best to make it short...and I am French so pardon my English!
I usually go online to talk to people but nothing really serious, I am just having fun.
This time a girl liked my profile so I decided to chat with her and we instantly clicked. We quickly exchanged email addresses to finally live chat on skype.
At first, we only communicated on the evenings but we did our best to make some time for each other and be able to chat on the afternoons. We spent hours chatting and getting to know each other. The more I knew her, the more I liked her.
I gotta say that I am 24 and she looks really young but she is 12 years older than me. She lives in the U.S and I am in Paris. We were not afraid of the age difference, we really felt confortable talking to each other. We also where ok with the fact that she lives in the U.S. and me in Paris. I travel a lot in the U.S. and in Africa so does she.
When we started to chat, she was in South Africa for business. After a couple of weeks, she told me that she wanted to come to Paris for a week or two to meet me in person before going back to the U.S.
We continued to chat, to have fun, to get to know each other more and we were planning her visit. I really was starting to have feelings for this girl.
One day she told me that she had problems with her business in South Africa and she was afraid to loose it. She was really busy and a bit depressed but she kept chatting with me 2 or 3 times a week.
I met her online in June and mid August I stopped hearing from her. I tried to email her, text her but nothing. She disappeared and I have no idea what happened.
It has been a month and a half since she stopped answering my emails and texts and I can’t take her out of my head. That’s the first time I feel like this for a girl and it’s killing me to feel this way for someone I never met.
What if something happen to her, is it someone who just played with my feelings, or was it a fake profile… I don’t know what to think anymore!
I am not a naive girl and I don’t fall easily so I don't think I am lying to myself when I say that we really hit it off.
I don’t really know why I am posting this, I guess I need to know what strangers think about this situation cause I am totally lost...
Thanks for reading me guys!