6 year old cat starting to be more needy in middle of the night?

My cat is 6 years and 7 months old, I've had her since she was 3 months and she was always the kind of cat that would follow you around, but wasn't a real lap cat...wanted to be pet only when she allowed it, for a few seconds, kind of did her own thing. She has always slept at the bottom of my bed and never disturbed me. in the past few months, i find her meowing and walking on me in the middle of the night, or nipping my arm for attention and waking me up. I'm having trouble getting a good nights sleep. I have no idea why the turn around; i don't think it's her not getting enough attention because i actually work far less hours than my old job (im just at an internship now) and im home a lot and play with/spend time with her, and she wasn't like this with my old job. It was cute at first, but now it's really affecting my sleep. Any clues as to why she'd suddenly have a different disposition after 6 years?