How much contact should my GF have with her ex?

I need Help… My Gf and I have been dating for alittle over a year. Her and I started seeing each other just before she ended her relationship with her ex boyfriend. They have a 2 year old child together and she keeps telling me she cares and loves her ex boyfriend,but she is in love and wants to be with me. They talk and text almost every day and I would like to know is that normal ?Now she was telling him for the first several months that her and I are just friends now she tells him that her and I have dated a few times and it’s driving me crazy. I ask her to just be honest with him and she says he knows that her and I are together and why should she tell him. she says she has told everyone important in her life ie kids,family and friends. She says her ex doesn’t care what she does and she doesn’t care what he does so why would she want to tell him. I tell her I understand they are going to have contact in person and on the phone because of the child, but I ask does it have to be every day. Also she says if he calls her for something she will always be there for him because thats just the way she is. She even says it took her 3 years after her ex husband and her split up before she stopped cooking, cleaning and being there for him. I do not understand this type of behavior am I wrong for getting upset?????????