My SO and his family don't want me to have the baby and he acts like I should be okay with it but…

My SO and his family don't want me to have the baby and he acts like I should be okay with it but I'm not . He also says I treat him different but i feel like I have to defend myself and child now that he doesn't really support me right now . I know after a while he will be okay but I don't know how I'm suppose to feel about him right now when I already love my baby and is excited .