Hambeak,
My kids are just a little younger than yours and the shunning has been going on for several years now. I understand the pain you're going thru. I decided long ago, despite being treated as tho' I was dead...I would try and keep some kind of communication going. I discovered recently that my good 'christian' JW x-wife had intercepted almost every letter and card I sent to my kids -- and then used that as "proof" I didn't care about them.
I cannot give details, but, every chance I got to just simply say...in spoken words or written..."I love you, I miss you and when you're ready...we can talk about anything." I always tried not to force them to listen, but, just left the invitation open.
The slow easy approach has finally started to bear good fruit, during the last year things have improved greatly between us and she is trying her best to get the others to start talking to me again. One of them hasn't seen or spoken to me for 5 years. Lovely religion.
Don't give up -- Never Surrender ! You may not know what's going on in their minds for a long time, but, I believe they will remember every effort you make. Show them a successful, happy person that does well -- without the WT in their life. That mystifies the hell out of JW's. And it's not easy to do when you have depression, too. One day they may realize that and show up on your doorstep -- like one of mine did. One so far !
Rabbit