First, I'd be really happy to see that she likes and bonds to other people. That's a great sign! I'd be much more worried about a puppy who was shut down and not responding to anyone. This sounds like a temporary glitch, although I understand that it feels a lot more heartbreaking than that.
Second, I don't know why your puppy finds interacting with you more stressful than with your boyfriend. If I were there and could actually watch, maybe I'd notice something...so it might be worth looking for a nice trainer to work with for a bit, to get the help of another pair of eyes!
Sometimes, we tend to put more pressure on a puppy than we think. It might seem like positive attention from our point of view, but feel stressful to the dog in some way. Even just being called over for a cuddle or treat might be stressful, if a puppy is new and feeling a bit overwhelmed. It might be worth changing your approach for a bit, and spend more time ignoring the puppy. If she approaches, give her a little gentle attention or a tasty treat, but led her set the tone for the interaction.
No matter how young or old a dog is, moving into a new home involves a lot of changes. It takes a dog a long time to settle in, bond to the new family, and truly feel comfortable. And it's normal for friendships and relationships to take a long time to grow! When I got my dog, I bookmarked this blog post from Dr. Patricia McConnell and read it several times a week for the first few months, to remind myself that this is a process that takes a long time (link to blog post: Three Ways to Confuse a New Dog
). Six months later, and I am finally feeling like my dog and I are really starting to click!