Daughters anxiety over her relationship with her father

[Bridget12]

My 8 year old daughter has a contemptuous relationship with her father. I won't go into all the history as I don't want to write a novel ! She feels abandoned let down and unfairly treated. Her father has never attended ant of her events such as award presentations parents evening etc and can be described as lackluster at best. She sees him every other sat and we'd evenings at his request he did have more visitation following 2 years of unnecessary court proceedings but one month after court finished he reduced his visitation. He has 2 other children from another relationship and a step daughter from a different and current relationship. My daughter is angry at him to the point the school have noticed she is becoming withdrawn and are offering her counceling. I get on ok with her dad and have offered more than necessary support and advice however he makes initial changes then drops back to the same old thing after a week or two. Issues started when she was 2 ranging from missed visitation, failure to recognise her feelings, no interaction during visits, broken promises and her not wanting to see him. his other children are expressing the same problems too. My daughter is very advanced both educationally and socially the school have assessed her as having the mental age of an 11-12 year old.Any advice on how I can support my daughters emotionally would be appreciated. Happy to give more details.