Disappointed and jealous

I have really bad baby fever, my SO is fiercely against trying again since we already have 2 children together(2 boys 3 and 5) and he has a daughter from a previous relationship. A few years ago he said he would be willing to try again and now its just a solid "nope". It makes it so difficult when a bunch of my friends (including my best friend) are pregnant, even seeing women on here getting pregnant..I want to be positive and happy for them in their success but, I can't help but be envious....

Just needed to vent.