That is exactly the same age this started happening with my daughter! I went hunting all over the internet looking for reasons. It seems it was just a very normal thing for that age. Newfound awareness and distractions during the day and growth spurts were cited as major factors.
We also cosleep, and that period was exhausting. But trying to sleep separately was worse! I did this "test", where I would put her to sleep normally in our bed (where she was nice and comfy, she would never tolerate a crib, ever. We had one collecting dust until we finally sold it), and then I'd sleep on the floor next to the bed (or on the couch in the next room). Daddy was in the bed with her too. So she was safe, but couldn't smell my milk. When she woke up, I'd feed her, wait until she fell asleep, and go back to bed myself. Didn't do a darn thing. Instead, I slept worse b/c our sleep cycles were out of tune and I'd wake up from a deep sleep to her crying to nurse. Sometimes right after I'd finally gotten back to sleep. Ugh. YMMV of course.
I made sure to tank her up during the day and tried to keep her focused on eating when she nursed. I eventually had to use a cover in public places b/c she was too interested in everything else. I still have to do that. She wouldn't tolerate a cover previously, so I found that interesting! During the day at home, I'd have to lie down with her and nurse her sometimes to keep her focused and relaxed and make sure she ate well.
Eventually, she calmed down and nighttime got better. For a good long while, I never noticed much when she ate at night. Now (she's 9 months), she does wake me up a couple times when I need to change sides. But I simply move her over to the other side of me and go back to sleep. We still have periodic (random) bad nights, when I either go to bed too late or she's teething, or not feeling well... and it still happens if she hasn't eaten well during the day! So I still have to make sure I get good nursing sessions with her when she's too busy playing to eat well.
"This too shall pass" -- if it's driving you too nuts and you can't wait it out you can try moving her. I'm of no use in that area though, as I've never done it.
Best of luck!