My dog WON'T stop peeing / pooping in my house!!!?

I adopted a small chihuahua mix, I really have no idea what she is... anyway, she's small. She is 2 years old, I've had her for 1 year. I was told that she was crate and house trained. Not the case. It took me 7 months to get her not to pee in her crate. I am forced to leave her in her crate for most of the day other than taking her for walks / letting her out side to go potty. She cries to go outside only when she is in her crate. If she is out running around the house she finds places to poop and pee, including on my toddler's bed, toys, my couch, my bed...everywhere. Her vet says she's perfectly healthy. I have tried EVERYTHING. I hate that I have to have her in her crate all the time, but i don't have a choice. I can't have the mess in our house, sometimes I don't see her doing it and I don't find it until it's petrified. With a toddler and a baby on the way, I have to have a sanitary floor and play areas. I'm just so frustrated. I don't know what to do. =(