I am not in touch with my anti-natal class friends, nor with nursery parents... I did never go out fo my way to be friends with my sons' parents, yet I am really glad I took up various invitations and didn't actively avoid the opportunity to have a nice Sunday with adults I liked who have children of the same age.
I think that the UNREASONABLE thing seems to be the pressure to FORGE friendships, or actively avoid them.
I have done neither. They just happened, and actually, I'm glad I allowed them to happen.
op Your friend is, quite frankly, wrong. For me, if a friendship doesn't happen naturally it isn't worth having, so I guess I'm on the fence. I know people who 'friend seek' (like full on marketing friendship campaigns followed by a series of Frinterviews where at any point you may be 'dumped') and I know people who actively avoid the chance to be friendly, who flat out refuse opportunity to mingle, who don't give a shit who their kids' friends are and don't care who their parents are, and if they do meet, there's no fucking way they're going to be friendly, give an inch or feign any sort of interest in anyone at all ever because they're "ok" have met their friendship 'quota' and who gives a flying fuck that the children might actually like it if they were a little more open.
On the fence. I don't seek friendship, I don't block it. In 4 years of Primary School I've accidently made 4 friends, two of which are married to each other.
YANBU op your friend is a crackers as you, it doesn't have to be and 'either or' situation. If friendship happens, hurray, if it doesn't so what, to force it either way seems a little inflexible.