Spot on wisdom

The crux of this is it IS her job to tell you what her need is. All people are responsible for expressing their own wants and needs to others. The only way you're going to understand is through her communicating it and developing emotionally. Granted, she's probably told you/verbalized it before, that doesn't mean it really "clicked" for you or truly understood. Other comments on the 5 Love languages are also really great suggestions as everyone receives and shows love differently.

No personal experience with success, but as to what to do with your time : focus on you. Spend time with friends , read some books , exercise , go on adventures, pick up a new hobby. Regardless of the ultimate outcome, you will have some long term personal growth and development.