Lost and sad

So much has happened in last few weeks, basically having some suspicions which have grown recently I did some digging and found out that my husband has been most likely been cheating on me. Not an affair but more like him and his friends (all fairly well off professionals... Physicians, pharmacists, dentists etc) have been going for guys night outs or guys trips that turn into bringing girls back to hotels/rented homes (They are in 40's and 50's) partying hard with booze, drugs, sex etc. They are like sugar daddies to these college aged girls.
This seems like a lifestyle for him and his friends, not a one time thing. I found emails dating back to 4 years ago. I now feel like my whole marriage of 7 years has been a lie, I've never had suspicions until recently and have not been able to confront him as we had this big family trip to South Africa planned which we are currently on and I didn't want to ruin it for my kids sake. So here I am 3 days into the trip with almost 3 weeks to go and I'm just bottling everything up trying to put on a happy fake face everyday. My husband can sense something is wrong but I told him we can't talk about it until we get back. I'm so lost, this is my second marriage with the first one ending after four years of emotional and mental abuse. My current husband has always been an amazing man and father with so many wanderful qualities, he has always felt like my rock and I've always thought myself so lucky to have found him. He always told me the same as he was also in a miserable marriage before. He's always said, I was the best thing that ever happened to him. Now I feel utterly betrayed, confused and lost. I saw my whole future with this man and now I Don't even know what my Future is. How can the person that brought so much love and happiness to my life be the one to bring me so much hurt and pain.