another sad turned out ok day

My daughter has been planning on ging to a Big Time Rush concert on 2/25/2012 since November when we bought the tickets. My 5 year old grand daughter is also going. I had a big problem with my daughter and grand daughter driving through Detroit late at night in a old van, so she asked her dad who lives in Redford if she could stay at his house, he said yes no problem, well the night before the concert he told her no they couldn't stay she was so upset she cried. I was very upset, mad, and disappointed at her dad. I almost told her she couldn't go to the concert she would have been devastated.
I just don't understand why her dad is always either ignoring her or treating her bad. He has a daughter by his second wife and a step son they are both disabled as are his 2 grown adult children, but for some reason when he got remarried he stopped being a "dad" to them. He was always the grestest dad. Takign them to the park, ball games, picnics, playing cathch whatever they wanted. I woked 2 jobs and wasn't home as uch as he was.
Then he got married and it was like wow he wasn't thee for them anymore. I do not know what happened. He thinks that since he has 2 children with him and his children he had with me can fend for themselves, and they can't.
I was so mad at my first husband for almost making hte grestest thing in my daughters year not happen.
This may sound harsh but I told my daughter she needs to not do anyhing with or for her dad ever again, becase he has disappointed her so many times she needs to stop letting him break her heart.
I hope one day he realizes what he has missed not partisipating in his childrens lives(when we divorced the children were 11 and 13) my children have been a challenge, my daughter with her bi-polar and ADHD, myson with his sczophrenia, ADHD, and anxiety, We have always had to raise them a little differently than other children, school was a challenge for my son he has been vbery smart but becase of his disabilities was put into a special ed class with regular work. He has made some very good strides recently moving into his own apaprtment, and volunteering at the hospital 2 days per week. My daughter lives with me she has a hard time keeping a job and I worry that she can't live on her own.She does jelp me out some taking me where I need to go, and helping me wiht laundry and I appreciate it. But children need their parents no matter what age they are, I am 44 year old and I still need my mother for many things. So I hope their dad stops and thinks!
thanks for reading more to come!