My husband now is refusing to go through with surgery to remove a tumor on his brain....?

My husband and i have been married for 4 years he is 25 and i am 27. My hubby tried to kill himself about 8 months ago and has been battling depression for awhile and well he has been getting better and then i had our son about 4 months ago and then he went down hill again.Well he collapsed at work about two weeks ago and they rushed him to the ER and they Ran a CT and MRI and a cat scans and found a tumor on his brain well he is scheduled for surgery on Friday well i put our baby boy to bed early and he wanted cuddled so i did because i am scared to so i know he is deathly afraid and its the only way i know how to help him! Well he told me he doesn't want to have the surgery and that he is scared and thinks he is going to die and doesn't want to leave me or our baby boy. And that he rather live with the tumor then die and leave me and the baby and that he was sorry for trying to leave me and he was stupid for trying to off himself. I don't know what to do to be honest its just so hard and i am super scared. What should i do? Advice?