Sarah, please don't blame yourself for H's behavior. It does not help you. You did a good job with the M and the kids, the best you knew how. Nothing you did or didn't do justifies what your H is doing now.

M: A really long time.
Crisis: 5 years.
She's still worth it.

Life is never made unbearable by circumstances, but only by lack of meaning and purpose. -Viktor Frankl