depress-
I strongly oppose to your idea of making a trip to see the woman. By doing so, you're giving her 2 much credits than she deserves, who is merely a common "gold digger".
I could use another term here but Paddy may fault me again. Wink wink.
Further, you will waste your hard-earned money for this useless trip. It won't accomplish anything besides you may end up being humiliated in front of your kids when you confront her. This may scar them for life.
The source of this problem is not the woman in VN but rather it's your husband, who can't seem to keep his ---- in his pants. Until you slap some senses out of him, otherwise, kick him out. Make him pay alimony & child support. After these deductions, he won't have any $$ left on his paycheck to send back to her, let alone to make a trip to Nam.
What's a point of keeping a hubby, a father who's willing to forego everything for a young pair of lips. Stay strong. Seek support from your family members or friends. It may be easier than you thnk once you let it out. You deserve better.
Write to me if it makes you feel better.