surrogate

So my best friend of 20+ years recently mentioned she would carry a baby for me and my husband. It was just random and I didn't think much about it... honestly not at all. A few weeks ago we were at another friend's wedding and we're both a bit intoxicated and she brought it up again, this time WAY more serious. She also took my husband outside and talked with him and then talked to me in front of my mom. We've been trying for a baby since our miscarriage 4 years ago with no luck. Partly from work and school schedules, but not sure that's the only reason. Has anyone had an experience like this? I'm a type one diabetic and 33 years old so the longer we try, the more risks and complications. I scheduled a doctor appointment for labs to make sure it's not because of my health. Looking for advice. How do you ever thank someone enough for an opportunity like this?? I'm so confused...