Hello! I saw no one replied here, and it's been awhile since you posted this, so I figured I'd try to help you out.
When she pees when your boyfriend is around, does he also do the "NO" and take her outside or to her pee area if he catches her type of thing? If he is not able to keep a close eye on her, she should be in her pen/crate with the peepads nearby so that no accidents can happen around the house, and she'll learn to hold it or go on the pads. She may have gone in the house when he wasn't looking, and so she's starting to think it's okay. So again, if he cant watch her consistently for signs of going pee in the house, then she should probably be in her crate or pen.
As for peeing a lot at night, do you let her drink a lot of water prior to bedtime? And by "a lot," how many times do you mean? Depending on how old she is (I take it she's still young), then they do pee a lot more at night than most older dogs cause they cant hold their bladders as well. But if you want to add the peepad training, what I do is I keep my Luigi in his crate at night, and when I first got him..every 1-2 hours or so, I would let him out of the crate and take him to his pads. Gradually increase the time, so your puppy learns to hold it longer. Now Luigi can hold it up to 4 hours or more, which means I get up less at night
He's 3 months.
If I'm gone at work (i work nightshifts at the hospital sometimes), then I don't leave Luigi in his crate, but I just keep him in his pen. He knows to go on the peepad, and at least he's kept in a smaller area so he doesn't go peeing all over the house.
I hope this helps you a little! Good luck!