"Prayers don't work" & "I told her to drink beer instead"

These two statements were made just this week by my neighbors. I found myself dumbfounded by the statements, and unsure of how in Godly wisdom to answer them. The "I told her to drink beer statement" was made by a mother to her 16 year old daughter who confessed to drinking "just" vodka. The mothers reply was of course "drink beer instead, it will fill you up so that you don't get drunk as quickly as on vodka." Huh...I just, I just didn't know how to respond to it.

My other neighbor has a daughter sick with cancer (18 years old), who seems to be on a suicide mission because she can't cope with life right now. I said to my neighbor "I'll pray for you" She replied through tears "They don't work! I know prayers don't work anymore." Again words failed me. As I stood there with nothing to say to someone hurting and believing all hope is gone. Will I be faithful when God answers my prayers about a life or death situation with a no?

Will I be more prepared when the Lord gives me opportunities like this?