I'm terribly sorry that you are in this situation. You've been betrayed and are rightfully in very much pain.

I hope that you can find peace soon. Meanwhile, I think that you need to get tested for STDs. His being away for two-week periods regularly gives him ample opportunity to hook up with other women for sex. Based on his secretive contact with the woman you mention in your post, it's quite likely he's been having sex outside the marriage. Thinking of you.