This may or may not help. I went through a time period with my mother when the words "I love you" could not come out of my mouth. It felt unnatural and not normal. But through some challenges and heartache in my life I did come to say I love you and developed a small appreciation for the love God had placed in my mother. However, times have changed and this love has disappeared and she has turned to be a harmful person in my life. But know that it is normal what you are sensing. It also depends on how old you are. Your mother's natural love and affection for you will most likely change depending on your age and what you are doing with your life. So, be prudent, use your best judgement, honor her, but be careful.