You want to spend all your time with her
If you are going through a phase of wanting to meet and spend time with only one person, then you are bitten by the love bug.
People in love often don't feel like meeting friends/family. They simply want to spend all their time with the person theylove.
If you are going through something similar, it does not mean you are some crazy obsessive person, but it means that you want to get to know her better and be around her all the time.
So if you find yourself making plans with her and only her every weekend, then you are in love.