I think your loss is fantastic! It averages out to about 4 pounds a month, and that's really not bad. I know that when you feel like it's going to slow, it's just not going to help to have people tell you your loss is great, though. And when you want to get there now, you want to get there
now. 20 pounds in 6 months is really something to be proud of!
I'm a super slow loser, like a pound a month, so I'm jealous of your progress!
Be patient, you're going to get there. Don't give up! I think it's great that you and your friend are working together, and you have a weight loss buddy. If you are both on the same page, and can support each other, you're doing great.