How did you get over being sad about moving your toddler to their own room?

My husband works nights, so he's not here at night. My 3 year old has been in bed with me since he was born. My 17 month old has been in his own bed next to mine since he was born.

My unexpected third is due in July. I don't have room for all 3 kids in my room and my 17 month old won't sleep anywhere but his own bed so just bringing them both into my bed wasn't an option. And I want them used to being there by the time the baby is born so they won't associate getting kicked out of my room with the baby.

My husband was off the past two nights so I wasn't alone. Tonight is my first night alone. Both of my boys are asleep in their own room. They went to sleep an hour ago and I'm seriously in my bed, eating donuts, and I can't stop crying. Mostly over my 3 year old because my 17 month old slept in his own bed and he doesn't want to or like to cuddle to sleep like my 3 year old does.

He's been in my bed for 3 whole years. I'm so sad that he's gone. How do you stop feeling so sad or guilty once they're gone? Especially when your husband isn't here at night?