How do I deal with separation from children? They live in another country due to divorce

This is a multi-faceted question.I have two children - a girl (5) and a boy (3). They live in China with their mother, we were meant to share custody, but she has since reneged on this and will only allow visitation. I moved back to my home country and it’s extremely expensive and takes a long time to travel back to China.I call them twice a day, every day. In the morning, 3am for me, and again in the evening, 2pm my time. But over the last 4 months the children have expressed less and less interest in spending time with speaking to me, in fact most days I simply watch them play and we don’t even speak. I’ve tried reading them books, I bought identical copies for them in China, writing them original illustrated stories, making them personalised videos, but I’m struggling to connect with them more and more each day.They are only exposed to Mandarin these days and my daughter now prefers Mandarin over English and my son hasn’t started speaking yet. They are being raised by their grandparents, with my son going back to my wife’s apartment every evening and my daughter spending most nights at her grandparents.They’re also being spoilt rotten. They’re constantly in front of the TV, for hours on end and they are hand fed. The default parenting style is bribery, with my daughter (who’s learned how to manipulate her mother and grandparents) eating ice-cream, chocolate, candy and biscuits (cookies) at 9pm\10pm. My ex is at work the whole day and only come back in the evening to take a child\children home.My son was going for speech therapy when he lived with me and I was potty training him, none of which is being done anymore - they don't have the time. My daughter was going to a private school, now she spends as much time at home as she does at play school because her grandmother thinks it's too cold, too hot, etc.How do I deal emotionally with being separated from my children who live in another country?Is there any way to foster a stronger relationship with them remotely?How can I instill proper manners and values in them? If this is even possible.I haven’t gone into detail regarding the reasons behind separating from their mother. Suffice to say, based on recommendations from professionals it would be best if I did not return to, and, had as little contact with my ex-wife as possible - for both my mental and physical well-being.I appreciate you taking the time to read. via /r/Parenting https://ift.tt/2SVCY0x