Dealing With Jealousy While Pregnant

So I've been having this jealously issue ever since this relationship has started some days I am able to deal with it better than others but most times it really bothers me. My husband has twins and I'm really not sure if I'm jealous of them or the baby mother. Every time they talk on the phone I huff and puff roll my eyes suck my teeth I get such an attitude and it just changes my whole mood. When he mentions the children I'm not too thrilled with the fact that my first child isn't our first child it just bothers me. I don't know what to do. Most people will probably say grow up or you knew the situation before you got into it and yes all of that may be true but I'm far past that point some may say I need to grow up and blah blah blah I'm just looking for some positive support, advice, and or feedback. If anyone cares to help. Thank you. 😪