Hi, my father left my mother when i was only 2. He moved 2 streets away and never bothered about both myself and my brother. Dont give up on your children. If i were you I would contact your ex and ask her if it would be alright to keep all communication open with your children. Id write them letters, email and phone. The year you spent away from them has obviously caused a breakage in your relationship, it is quite possible that your daughter may feel you wont be around and that you may vanish again from her life. I dont think she didnt want you there, it might have been her way of asking you to prove youll be sticking around. Again, id write her a letter on a weekly basis, make sure its address to her directly, which paves the way for her to feel that 'this is a lettter from my dad', this will give her, over time, a sense of belonging. i would also email them, if you can, every night, just a quick how are you, hope you had a good day, night night. that sort of thing. in time your children may wish to visit you at your home. After a few weeks of letter writing, just casually drop it in that it would be nice to see them again, tell them that you like germany and would love to be shown around by them.
Its a difficult situation, but if you handle it carefully im sure youll get there. just dont give up on your kids