Its really too bad to lose your true. when you lose trust in someone its really hard to retrust him/her again. but I think he doesn't have courage to tell you that and were thinking he is gonna break your heart if tells you about his past with civil wife. I can understand you how does this hurt you. but you both should be honest with each other and try to slove this issue and try to break the ice and talk to him straight away about this. there should be no secreates between couples.
wish you happy life. you have a nice smile and cute kid.