Hi rky, I agree with papa's wise advice, and would like to offer another thought.

Has W had any holidays with GF? This might be something she needs to get out of her system or forever feel like she's missed out. My W is on holiday with her GF as I type, and I know how much she feels she needs to do this. We have no kids, let alone one with special needs, so I understand that adds an entirely new dimension to things. Still, if there is any way you can swing it, you might be surprised to find her quite grateful for it. Talk it out with her and see what you all can come up with.

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