"It makes me very glad we've hardly told anyone if that's how people judge you if you're infertile."
You are a better woman than I am, OP.
Granted, I only had to deal with secondary infertility, rather than primary - but I could never have stood for what you've dealt with here.
I dealt with my infertility issues with brutal honesty and I would have taken this kind of 'friend' to task by spelling out my every failed treatment, every miscarriage, every disappointment, every distressing episode (in my case, there were many of each) and asking her point blank whether she seriously believed what she was spouting.
Whether she really thought that my DH and I were actually incompatible simply because we were struggling to conceive successfully.
Whether she really thought that the very many fecklessly fertile (and quite frankly often abusive) parents out there really deserved multiple babies when I couldn't have any. Or the easily-fertile-but-couldn't-really-give-a-shit ones.
I would have deliberately set out to make her feel guilty. Guilty and undeserving.
I would have wanted to watch her squirm. In your shoes I would have socked her between the eyes with every painful detail of my own situation and made her squirm.
As i say, you are clearly a better woman than me, because all you want to do is stop seeing her, rather than taking the nasty little madam to task.
My view is that she doesn't deserve her three easily-conceived children - and you do not deserve to feel shite because of her pig-shit-thick opinions.