Dear Massi,  Please advise. There's no issue between my mum and wife. They both seem to get on. But I've noticed in the last two months, every time my mum invites us round, my wife suddenly develops a headache and doesn't go.

At first I believed her, but now it seems to be way too coincidental.

I can't confront why wife and accuse her of faking headaches.

But my mum has started making comments about it too.

What shall I do?

Massi says,  It is natural that you want to maintain harmony between your mother and your wife.

Speak to your wife in a non accusatory manner and invite her to talk to you about how she feels.

By avoiding going to see your mother, your wife is expressing a degree of anxiety by using a headache as an excuse to avoid interaction. 
By allowing your wife to communicate her thoughts, you can help her to find a way to feel more comfortable when visiting your mother.