Where has my good sleeper gone?!?

From 6 weeks - 6 months, she has slept through the night. Took her last bottle around 8:30, would be finished and in bed by 9. Now, 8 months old, she has only slept through the night 3 maybe 4 times in the last 2 months. She's waking up between 11:30pm-1am to eat, and then again at 5-6am to eat again. This morning, she woke up at 6 and ate and was ready to play. Now it's 7:45 in the morning and she's still playing. What is going on?! I've tried everything. Do you think it's because we share a room with her? We live in a two bedroom apartment and our older daughter has her own room. Should I try moving my 8 month old in with my older daughter to see if that changes anything? My husband and I can't do anymore little/ to no sleep nights anymore.