8 month old sleep HELP

so our 8 month old was sleeping through the night completely since about 5-6 months ... 8 months hit and all the sudden she wakes 7-10 times a night. no lie. i'm so confused as to what is going on. it's been 3 weeks now. at first i read maybe she's not eating enough solids so we started giving her more/letting her feed herself (as she was already crying and stealing food off our plates), that seemed to work for a night but that's it. then she stopped taking as much formula which seemed to me like a good time to knock out the night time bottle about 3 days ago ( the only bottle she gets) she's been on sippy cups for the last 4 days until i just caved right now at 11:30 after the 4th time since 8pm she's woken up screaming. what do i do?! is there anything to do?! will it pass?! is she missing her night time bottle?! we have been doing so good without it, or so i thought :/