Hi, I too am in my 50s. My mother and myself weren't close; I found out in my 20s I wasn't planned, she was 6 months pregnant, and nearing 40 years old when she found out she was having me.. Her mother lived with us at that time and gran brought me up, I feel I was closer to Gran, I never felt mother and myself bonded. Gran passed away when I was 10 years old, leaving an adolescent/estranged mother relationship. She never hugged me out of love, I would always have to ask for a cuddle. Her philosopher a mother was, I feed you, clothe you and dad puts a roof over your head - end of duties.
Now I always tell myself it's not my fault when I start to feel guilty for not loving her, and not too upset when she passes away, though she had Alzheimer's, so it was a blessing really.