wao, I'm so sorry ... it's really a very strong situation ... but as you mention it ... true marriage is a strength, where the couple goes through good and bad times, and the most beautiful of all is the mutual support, understanding, help, empathy between the 2 ... that strengthens the marriage .. It's good that you're with her, and you're there, doing your husband's role very well! That's what it's about ... I'll be praying for your mother-in-law, so that God will take away his illness, if you can take her to a Christian church. For God there is nothing difficult ... faith is very important. I will also pray that God will give them great strength and help them in everything they need ... Blessings.