I dis like her

So me & my boyfriend had a fight I once uploaded about finding out my boyfriend had another baby prior to mine , so I recently express to him I am not to fawned of his mother . Now I am all for protecting your children but right is right and wrong is wrong . So I basically did the math and from what he said when he found out  the mother also knew about him having a child and kept it a secret & I have asked her during the time she found out too if she had any grand children & she said no. Now I'm really upset at her because I don't think that was woman like & respectful of her to sit there look me in my face laugh , smile & hold my baby (I have with her son ) while she knew the whole time what he was doing . He also told me that he told them I knew about the kid so they wouldn't bring it up but I think he only told the father that because he not to close to his father and he told his mom when I first got pregnant &asked her not too tell his dad and she didn't they hid it from him until I was 7 months. So am I wrong for it wanting to go over his house until he moves away from his family house nor do I really want her holding my child ? And how would u feel if u guys were in my shoes