Friends jealous of pregnancy

My fiancé told his best friend that we are expecting, and his response was to say that his wife probably won't want to talk to us or want to hear about the pregnancy/baby because after her cancer treatments she has minimal chance of conceiving naturally to have a second child.

I'm slightly offended. This is our first, and friends are supposed to be supportive! Not to mention that she CAN become pregnant through IVF or other methods.

Am I wrong to be upset? We were there for them through her cancer treatments, and have always been there to lend a helping hand.