Originally Posted by Jcon
If your feelings are returned... I'm not really sure what more you'd want.
Originally Posted by polywannacrackeryo
But Iíve begun to fantasize about coming home to her and spending the rest of my life with her.
I think she made it pretty clear what "more" she wants.
Six months isn't a whole lot of time for things to settle. It's pretty common for emotions to fly rampant for that amount of time.
But Jcon makes a really important point about kids. Forget all the other issues for a minute. They're having kids, you don't want kids. Presumably that means you don't want to live in a household full of kids. So based on that alone, moving in with them ("go big") is pretty much off the table.
It sounds like you really need to sit down and discuss the jealousy and "the life you'll never have" with her, and how you feel about all that. She needs to know everything you've told us. She believes you don't need to fear your emotions. Presumably her reassurance is coming from a different perspective, out of context with what you're telling us. But from the sounds of it, I think she'll be supportive of you through your struggle.
As you've said, you're not trying to change their marriage or take anything away from them, you're just mourning a life you'll never get. As long as you make that clear, and let her know that you just need to figure out where you fit in so that your heart isn't broken, I think you can work it out.