I know you're feeling unappreciated now, believe me. My son and daughter both went through that phase too. But, with time, they were able to see for themselves how their Dad was. I never had to say a word.
Today, my kids have turned into wonderful, appreciative adults. My son calls me at least twice a day. My daughter, not so often, she's raising two kids of her own.
Just wanted to say, that it can get better! hugs!!