I Major General in the Army told me at his 30th Anniversary that the secret to his marriage's success is to never be home for more than 3 days in a row. Funny story, but true in some ways. Time apart can improve the value of being together when you're home, instead of just punching a clock every day and waking up at 6am to go-to work and come home, eat dinner, and go-to bed together having not really had quality time. But the relationship needs to be able to tolerate that time apart to make it to that enjoyable time together.

In the end, no matter what anyone says it's more important that you ask yourself how your wife and YOU will handle being apart. My wife is strongly independent, faithful, and misses the crap out of me when I am away so when we're together it's great. If you're with someone who feels "incomplete" when you're away... they will likely struggle to adapt. While you're out flying to Beijing and eating exotic locale, she will remain in the same place probably eating KFC and wishing you were home. On top of that, if they're a martyr type... they will suffer silently for years without you knowing the impact it's having on them.

It's all about you and her. Strong marriages and strong couples can get through anything if the situation is right and you all are on the same page. It's definitely not the job itself, but you have to make sure you and your relationship are compatible to that job's lifestyle.