Thanks for the input so far.
Several of you have made suggestions that I have considered, including his perception of our relationship and his childhood.
I have discussed those things with him and apologised for those things that I think he might have found difficult - a difficult divorce when he was very small, his father was abusive to me, my longterm health problems - although when I have brought them up, he has replied with variations of ‘It’s fine/It’s OK.’
When he became depressed and anxious a few years ago I paid for therapy for @ two years although he was working full time in a well paid job. So I think that I have acknowledged the potential that it is due to me and tried to help him see my willingness to discuss things and accept responsibility,
The visit that we suggested was just to see their new house, we weren’t even expecting lunch on the day, so I don’t think we are ‘pushy’ or demanding. We never say anything about the difference between how we are treated and her parents. They are adults and it is their choice of course.
I am very careful to allow him to run things his own way and to respect boundaries, but I just wondered whether it is unreasonable to expect a phone call asking how I am or more regular contact.
I guess I just have to continue to live with not seeing or hearing from him very much. I strongly believe in respecting boundaries and know that sometimes a family member is best avoided.
It is just hard and we do miss him.