Need advise on what to do and think?

K last week I posted a ? about what to do. My fiance and I had our first fight 3 1/2 weeks ago. She asked me to leave so I did. And she never called. She talks to my mother alot but not to me. She is the same age as my mom and of course I am alot younger. But on Valentines day I gave her a love letter and rose's etc., She said she loved it and said she would call me later so we could spend time together and she never called. It's like I am the one trying to make it work and she doesn't try anymore. She felt so distant when I gave her her gifts and I also noticed she was not wearing the engagement ring. What do I do and what should I think. This all happened all of a sudden and don't know why.