First stop and take a deep breathe. You have to get your head in the game. It is scary believe me, we had our baby and then three weeks later we were doing chemo, I shed a whole lot of tears myself especially those first few days and then one day I realized that I had to get my head on straight, that my husband and my family needed me. Take time every day to yourself to cry and be sad, you need to, but remember your husband is going to need you to be there for him, he is going to need you to be his caregiver. Remember that even though it has spread, it is still very curable. Stay on top of your husbands treatments, know whats going on at all times, listen to your husband, love your husband and try to make lots of wonderful memories together. Remember that if he gets grouchy with you that it's not you he is mad at, its cancer, don't take it personally. I think that's all I have for advise.
It's going to get better I promise, just take it one step at a time, on breathe at a time and fight fight fight.
Feel free to PM me anytime, I have been where you are sadly.