Platonic relationship with ex

I have been in a very loving relationship with my boyfriend for almost 2 years now and we plan to live together once my divorce is finalised. My ex husband was unfaithful to me and cut off my access to everything, phone, facebook, banking etc and became very secretive when previously we were completely open with eachother. I knew that when I got into another relationship I couldnt cope with all this secrecy again, and I would want my partner to be as open with me as I was with him. I trust my new man 100% and know that he would not go off with anyone else. I have discovered he still talks to his exes which are friends. I am fine with this, but find it hurtful that he didnt tell me until I asked him about it. He said he didnt tell me because he knew I would be jealous. Im not a jealous person and I said to him that I am fine If I know what is going on. He said we are going to have to agree to disagree on the subject. I have alot of stress in my life at the moment with Elderly sick parents and a nasty divorce, and wonder if I am getting too emotionally wound up with this situation, or should my partner be open to me about this? Thank you for taking time to read x