I know just how you feel.
I had the same trouble with my last dog, and the one I have now.
I think you're right about the reason she is doing this. She wants to be near you. You're obviously a great mom. That's what it's all about. She wants to have you within sight all the time. Dogs are pack animals and like to sleep with that special member of their pack.
There really is only one way to stop this happening, and don't worry, it doesn't involve filling the house with 101 labradors :). It sounds simple, but believe me, it's a tough thing for you to do when your mommy heart strings are being pulled by this heavy little bundle.
You need to let her howl for a few nights on the trot. I know your neighbours and you and hubby will not get much sleep for that time, but it will work in just a few nights if you stick at it.
Give her the same bedtime routine every night. Put her to bed at exactly the same time. Say night night to her. Cover her crate with a blanket. Turn out the light and don't look back! Do not under any circumstances come downstairs when she howls. Use ear plugs or listen to your mp3s, anything, but just tolerate that howling without giving her any kind of attention for doing it. If you lapse just once because you're worried about the neighbours' complaining, she will take that as a message that if she howls for two nights in a row, you will come running. So never go down to her while she is howling.
You'll be surprised at how soon she learns to sleep in her little crate till morning.
The one thing you have on your side is that she's still a puppy, and puppies are very adaptable. She will learn, believe me. But she is depending on you, as leader of her pack, to show her what is expected of her at night time.
And I hope you will be enjoying some peaceful sleep in a nice comfortable bed again soon.