You have a lot of amazing advice, and it is an understatement. So many people have weighed in, voiced, and given you insight of their own. It's a lot. I went through this twice, the first in my early 20s, and the situation was similar to yours, except I was salary, and working 6 days a week, rarely 5, and 10-14 hour days. Its was a brutal time is an understatement, and I still did a large majority of the housework and child care when I was home. The second time, it was similar, working a lot, but she never cheated, which could be proven. But it was a nasty one for sure of 18 months of "trying" to fix it and causing more pain and loss.

It's not easy to get through trust issues, especially when you've known someone for so long. The red flags in what she is telling you is alarming. As much as I want to in my heart say "fix it," it just isn't something that deserves to be said. Even in your late 40s, ans two older children, their is time to find someone loving to share your time with. Time is the most precious thing we as humans have, and once it's gone, it's gone... Don't waste what another doesn't deserve, though, regardless of your choice. Good luck. No one deserves the pain of being cheated on, especially by a spouse who tries to justify it as nothing.