I went out once per week and went out one weekend a month with another friend (male) and usually one week during the summer with two or more male friends. We worked hard and had a blast. During the one weekend a month we'd go fishing or floated down a river or camped out in the woods. We'd go for hikes of one to 10 miles at a time.
My wife supported me completely and encouraged me to take the time out on these outings.
Oh, I just re-read my comments. ;-D. I forgot to mention I was a Scoutmaster and the other male was my assistant scoutmaster and the men I was with on the weekends and a week at a time during the summer were the other adult leaders, usually the fathers of the 8 to 14 boyscouts we took with us and taught the basics of wood lore and life. We taught the boys to be self sufficient, and leadership. Many of them made Eagle Scout.
As a husband, I wouldn't even consider going out without my wife unless it was for the reasons stated in the above paragraph.
What can you do about it? Take a proactive stance. Act like you'd love it if he stayed home with you. When you see he is preparing to go out and your kids aren't around wear something soft and see through and frilly/lacy and ask him if he rather spend time with you. If your kids are around, close the bedroom door and ask the same thing OR follow him out to the car or truck . . . well, you get the idea. Unless he's a eunuch he'll stay home with you.
If you lack the knowledge of what motivates most men to give up the old friends and stay with his new best friend (you) read the book, "The Proper Care and Feeding of Husbands". Watch the movie, "Fireproof" and get the workbook. He'll wonder why he ever left. AND you'll know why and will have given him the reasons to stay home.
Are you not the woman you were when you got married? Remember, "A model needs perfect lighting, professional make up, and designer clothes to look as good as the average woman does to the man that loves her."
Good luck to you and yours.
P.S. Princess Cruise Lines was the setting for the "Love Boat" TV show for a reason. Think you can't afford a cruise? Brown bag for a year and save the $6 or so per day you'd spend on lunch at a fastfood joint or restaurant and you'll save enough to pay for a week for two on the "Love Boat". Have fun;)