Teenagers

I've always been really close to my girls, more so with my oldest. A mama's girl. Until recently that is. She just turned 17 and has been with her boyfriend for the past 8 months. Now she rarely is home and hardly spends any time with me and I'm having a hard time with it. Worse is that she spends more time with his mom now and I'm trying really hard to not get my nose bent out of shape.

You guys have any experience with this and any advice on how I can handle it without saying/doing the wrong thing?