Am I wasting my time? My girlfriend of 2 years only told me once early in our relationship that she loved me.?

She never says "I love you" anymore, when I ask, she says "you don't have to say it to feel it " She says things would be different if she had a ring on her finger, but I can't give her that commitment if she won't share her feelings and heart with me. I'm good to her and her kids. and I work hard to be a good provider. She still seems indifferent towards me. Though I tell her how I feel about her it seems not to register with her. I care about her and her kids and I'm working hard to develope this into something great. Her dad hinted about us getting married but I'm not going to chase her, I feel if she wants to be part of something that can be good she'll share with me. I've turned down several offers to go out with other women because my girlfriend has a really special place in my heart. But I still must go on with life and I want to know does she want to share a wonderful journey thru life with me or just keep me in limbo. I grow weary of wondering. and feel discouraged.