i've got a different spin on this...i have the same problem. i did tell my son how much i missed them-i live 30 min. away. it has not improved the situation. i have 3 grandchilren who i have not seen for a year. i choose not to visit their home due to my daughter in law. so part of this is on me but it's healthier for me to not be around her. now i just don't get in touch. my attempts to keep communication moving along falls on deaf ears and i decided why do i always have to be the one who makes contact? why have to BEG? CONCLUSION: if i was important in their lives their actions would show it. so i guess i'm not that important to them. the only time my son calls me is when his wife and children are out of state. go figure. my thoughts used to be on this...to keep the peace with wife he doesn't contact me. i used to give him leeway on this but in therapy we concluded part of this is on him. and he falls short!
so make the effort. communicate what you said here to them. then the way i see it if it falls flat...get on with your life.
sorry you are feeling the hurt as i did. it does hurt...a lot. but i realized i needed to let it go. it is what it is. i hope your outcome is better.
ps oh i'd definitely keep the ex out of this. that creates a "triangle" and is not a healthy, imho, approach for any of you to resolve this.