im pregnant again and so happy about it, so why cant everyone else be happy?

i just found out yesterday that i am pregnant with my 3rd child, i really have wanted another baby for a long time now but my husband has 2 grown up kids from a previous marriage and says to me that he doesnt want another. my own parents are trying to talk me out of the pregnancy because they are worried about the money side of things, but to me it wont be that much more difficult with another mouth to feed, especially as i plan to breastfeed. just feel so alone now like everyone is against me, and dont know what to do for the best. when people try to tell you what to do and your hormones are going crazy its so hard to think clearly :/