Cats are such amazing creatures.
And all with such different and unique personalities. One of my males, Duncan, will literally come and tell me when HE thinks it is time for me to go to bed.. He'll talk and talk and talk on endlessly until I ask him if he is ready for bed and then he high tails it up the stairs and jumps on the bed waiting for me to arrive.
Widget, my youngest is incredibly social and every time I have to use the bathroom, she has to come and see what is going on. Doesn't matter that she may be sound asleep upstairs, it's like she instinctively knows when I go into the bathroom, she must go too. And she always requires a few chin scratchings or pets from me while I sit and do my business. She always waits for me to finish and then goes back to her own business. Another quirk she has, is that she hates the sound of the coffee grinder in the morning, but she feels she must stay by my side until the noise stops. As she watches and hears the beans being poured into the grinder she begins meowing. I always reach down and give her some loving pets with one hand as I press the grinder button with the other. Again, as soon as the grinding stops, she is off to find other things to do.
It sounds to me like your cat is fast becoming very attached to you in spite of your boyfriend giving her attention and play. It could just be the difference in personalities that the cat picks up on. Your boyfriend could be the "playtime guy" where you are the "nurturing mom". Sometimes nurturing mom is needed more when they are young.
BTW....I have 5 cats and definitely need to get back to the Cat Room!