I suppose this might make you feel less put on the spot and give you a bit of time to think about it before reacting.
I miss you when you're not with me. The nights I come home from work and you're not there, I wish that you were. I know that moving in together is a large step, even without taking Evie into consideration, but I would love nothing more than for you to move in with us. My future is with you, I know that with my entire soul, and I want our lives blended in all the ways. I love you, Becca. Would you like to move in with Evie and I?