If your friend is dropping literally everything for her boyfriend, then you may have to wait until she realizes on her own how awful it is to forgo friends or anyone else in her life like that. Even if it takes a long time. Unless your friend is too blinded to see what she's losing by treating you this way, you may have to wait until one day she either breaks up with him or reaches out to you on her own. However, if you do keep reminding her of what she's doing, it'll most likely push her away, or her boyfriend might tell her you're getting in the way of them, which could end badly. Therefore, I really think you may have to wait it out... not the best option, but the only other option is to try talking to her when her boyfriend isn't around or try to make plans, so it's just the two of you. If that doesn't work, then yeah, you either wait for her or cut your losses.
It might not be the best advice, but it's what I got for right now. :c