A.J.
The way I've often gotten "my way" was to put my husband first. He's sort of a different case, as a musician, trapped in early adolescence in many ways along with "I'm an artist and the world revolves around myself and my own creativity" type attitude. Not trying to bash him at all, these were things I always knew, and as an artist myself, could relate, even though I have the nurturing instinct and care for others before myself-OPPOSITES!
Anyway, he did the old, "I never saw myself as having a family and kids..." and wasnt' happy about it when I got pregnant with our first. Inside, I was like, "Ya, duh, none of us though about kids in our 20's, grow up" (we started sort of late having kids, I was 35 and he wanted me to "wait a few years" and try again..?...) We were engaged, not married. We hadnt' been careful with birth control, so I was alittle annoyed at his shock. At the time, we were together in LA, but I still had my NY apartment and my career.
Anyway, rather than kick him to the curb, I told him with full compassion and honesty, that I would NEVER want a reluctant father for my kids, or to ruin anyone's life. He was absolutely free to go, and even though I loved him and would be so sad, I would not hold it against him or come after him for any child support (naive, but I made a lot of money at the time) he could go keep his freedom. As weeks went by with him moping, and me not having any of the fun and excitement newly pregnant ladies get, I put my own disappointment aside and just let him be. You can't change someone else, or make them feel how you want them to. He decided to stay, proposed, and started announcing the pregnancy to friends and family, and with all the attention, warmed up to the idea. This was a nice surprise, but I was fully prepared for him to leave as well. When the baby came, he blew my mind with his natural good parenting-he's better with babies than me. Our next two were accidents WITH birth control. He's finally more excited about his marriage and kids than his touring and band stuff. Even though with each new announcement, he freaked out, got negative and scared, and I reminded him the door to the outside world is always open and that we're here to love him not ruin his life. HOWEVER I'm not trying to get away form your situation:
You have to put him first if you are planning to stay with him. But also keep in mind, nothing is ever guaranteed, and you may not always be with him for many reasons. In which case, you will only have your kids, and should have what you want to be happy. He is feeling trapped, and doesn't seem happy to have kids. You need to address this with him. His kids are a gift who love him, and if he doesn't see it this way, maybe you need to compassionately find out if he would be happier on his own. Not in a sarcastic or harsh way, but show him genuine interest and ask him how his life would be in a perfect world. Spend the next few months/year making him your star and doing things for him to show him he's important and figure out what is going on and if you guys should be a team or not. Figure out how you really feel about him, if he's not nice to the kids. Put the third child thing on hold. Put him first. When my husband would imply maybe I should "not have" the babies, I put away my own disgust and hurt and realized it wasn't really about him. I wasn't going to "not" have a new family member and child to love of my own on his behalf, because our relationship was not a lifelong guarantee. No matter how happy you are, you don't know what could happen. I wanted the kids, and he was a free man. So far it has worked out, but again, I knew he was an awesome dad, so that fear wasn't there that he would be cold to the kids if he stayed.
You need to assess your relationship before entertaining the 3rd child notion, and yes, you already have enough children to be happy if you decide to be happy with that many children, but if you will always feel like you were meant to have more, you need to be honest about that with yourself and him and figure it into your vision for the rest of your lives. Decide if you want to stay with your husband. If so, you need to respect him, but he needs to come to terms with the fact he doesn't like parenting for the kids you already have. Not everyone loves kids, and he may be one of those people. You can't change that. Maybe reminding him he has his god giving freedom will make him realize he is not trapped and value his situation more. I feel the biggest shame in the world is people who don't appreciate their families, when so many people don't have them-if they can't have kids, or people have passed away etc. I told my husband if he wasn't going to value us, someone else would, and I wanted my kids to be loved. Best wishes I know this is really painful, I hope everything works out and that your family grows one day.