Lilly sleeps with us at night. She follows us into the bedroom whenever I say "lets go to bed Lillybug!". She snuggles under the covers usually either by my stomach or down by my feet. She usually sleeps straight through until we get up in the morning and will get down and go potty (pee pad trained) whenever she needs to. Our bed isn't high up though, I know if it was, I'd be afraid or I'd buy steps.
Whenever we leave, we put a baby gate in the bedroom doorway and she usually just sleeps on the bed while we're gone. Whenever we come in the door, she's there jumping up and down smiling and can't wait to come out and see her mommy & daddy.
We always tell her we'll be back in a little while... she doesn't bark or whine but it still breaks my heart some. Now, if I put her in the bedroom and she knows I'm just going out to check the mail or something, she'll whine & bark.
Hope this helps some!
Edited: We used to keep her in her crate at night and one night I finally just got fed up with it. It was hard for us to sleep because of the whining. I was scared we'd have problems with her sleeping with us but she adjusted very well & loves sleeping with us. I think you'd be alright & it's great to snuggle up to a warm little furry butt. :P