Is it normal to miss the sex i had for years with my mother?

Growing up I never had a male role model, father left and my mother refused to remarry so she could take care of us kids,working 2 jobs, and still finding time to do PTA at the school. At 16 I moved out to work and support myself. When I went home to visit after I turned 18 my mother and I got drunk and ended up having sex. The next day when we sobered up we talked about what had happened and agreed it should not have happened but she said to finally have a real cock felt so good which made me want to keep making her happy especially after sacraficing her self and happiness for me and my siblings I reached for her again and this time being sober was more intense and incredible for the both of us. For the 2 weeks that I was home it became an everyday 2 to 3x a day thing. I left and none of my siblings know. I eventually got married as well as she did too, but even that did not keep us from having sex. We lived in different states but visited each other as much as possible and make love until she passed away. I can't help but have fantasies all time about us.