i think maybe after telling you something as big as "you are the love my my life" triggered a feeling of fear within her, as she may feel anxious that you could be the real deal and she may be afraid that she has developed feelings for you that even she cannot control. she needs time to get her head around the idea be aware that she needs space also..you are the LOVE of her life, but dont engulf it completely.
"We all take different paths in life, but no matter where we go, we take a little bit of each other everywhere."