I'm Lucy, and I'd be happy to answer your questions today. I'm sorry to hear about your situation.
It's not illegal to develop a friendship with someone much younger than you, or to spend time with them. As long as you're not soliciting her for sex, exchanging sexual images, or engaging in cyber sex (or phone sex) with this woman, even if she turns out to be under 18, it doesn't sound like you've yet done anything illegal. Clarifying that your intent is to only spend time with her could help if she turns out to be a minor. At the same time, if you are charged with a crime, it will never be a defense that she lied about her age. So if you have any reason at all to worry that she's lying about her age, that's a good reason to reconsider.
You should be aware, though, that a huge percentage of young women online claiming to be in a foreign country and asking for money are actually scam artists -a group of men living in Nigeria or Ghana. If she really wants to come visit, she can pay for her own ticket, and having a credit card would make it more likely that she's over the age of 18. Because of the huge prevalence of online scams, a person should never send money to someone they met online, especially when they're claiming to live in a foreign country. The fact that she sent you her passport is actually MORE suspicious, not less - scam artists hand stolen or faked passports out like candy. I don't know any people in real life who would scan a copy of their passport and email it to someone who asked for it online. It really sounds like the odds of you being scammed are higher than the odds of you being charged with crime. Make sure you talk to her, on video, with sound. Have her show and hold up an ID with her name and picture. Do Google image searches on the passport she sent you and any pictures you have. Google any flowery or romantic language in the emails you've exchanged, plus her name. Get as much information as you possibly can. And it is a very bad idea to send money to someone you've only met online. There are just too many scam artists out there, preying on people who are looking for love.
If you have any questions or concerns about my response, please reply WITHOUT RATING. It's important that you are 100% satisfied with my courtesy and professionalism. Otherwise, please rate my service positively so I am paid for the time I spend answering questions. If you are on a mobile device, you may need to scroll to the right. There is no charge for follow-up questions. Thank you.