When I first got Chloe, my husband was away for 2 weeks in the field(US Army). I let her sleep with me because there was alot of space in the bed. I truely believe that is how she was able to get through the night without having to potty. I had to wake up at around 6am to let her out because she would wander around the bed and I knew she had to go. The older she gets, the longer she is able to hold it. When my husband came home from the field we decided to crate her at night so that we wouldn't squish her while we are sleeping. We made sure to just let her have enough room in the crate to sleep, and that's all. We crated her until she was about 9 months and then let her sleep with us again because we felt as though she was big enough. She will sleep half the night with us and half the night on the floor. Lol..
Now, with Andy, it's a different story. When we got him we crated him at night immediately. He would whine and we would give him a firm "NO!" and he would stop. He had a few accidents in the crate during the first week we had him but he finally understood that the poop was disgusting to lay in and stopped(thank goodness, I was tired of cleaning him and the cage!!). haha... So he has always been in the crate at night. He is 5 lbs, smaller than my Chloe who is 8.5 lbs. So I knew that it would be more difficult training him. We had to let him out several times at night in those first few months. I still worry about him having accidents because he's smaller than her.
When my husband was gone to Korean and then Iraq, I would let BOTH of my babies sleep in bed with me. For some reason it helps them sleep better and longer. During the summer when I wasn't working (I'm a sped assistant) they would let me sleep in until around 8:30.
It just takes time...but they will get it before you know it!