<human>: So obviously I've known my sister for our whole lives. In the past few years, she has gone through some terrible boyfriends - including a convicted sex offender and a guy who turned out to be a hard-core drug addict. The few "normal" guys that she's dated have never really lasted very long - she tends to blindly rush into things, convinced that this new guy is "the one".

She'll say that she wants an affectionate relationship, then date guys who don't touch her outside of sexual situations. She'll say she wants a guy with vanilla sex preferences, and end up with a sex offender. Her approach to dating is pretty naive, and she doesn't seem to learn from her mistakes - she doesn't even give herself time to learn - she's never single for more than a week or two.

The current issue now is that, about a week ago, she met a guy online somewhere (not 100% sure where), who lives in Canada (we live in the US). They met for a day in Seattle (we live close-ish), and apparently it was great. 

Awesome, happy for her. Now she's talking about spending a week with him in Vancouver (and taking a week off from school in the process - not the best idea given that it's her final year).

I'm not fully supportive of this - this guy claims to not have Facebook or a cellphone, which raises a couple red flags for me. I just feel as if it's not the best idea to go into a foreign country for a week with a guy you hardly know, especially if she has no way of really verifying if he is who he says he is - and they've only known each other for a week! I've tried raising these concerns with her, but she just says that he's not "like that". 

I'm the only one that knows - she hasn't told any of our friends/family what's going on because she doesn't want to deal with the "judgement" and I'm just really lost. I know it's not really my place to make these decisions for her, she's an adult, whatever, but I still worry.

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<bot>: my sister has a terrible relationship trackrecord and is now talking about spending a week in a foreign country with a guy she knows NOTHING about... should I do anything?