Interesting. My kids are also far apart in age, 10 yrs, and from different fathers. My d is 21, my s is almost 11. I am a very different parent to my son than I was to my daughter. Some of it is the fact that I'm older and wiser and a lot more patient. But they are very different children, like night and day. They both have challenged me to grow in ways I never thought possible. They are my biggest teachers. I also had locked away so much of my own emotions since my dysfunctional childhood, growing up with likely BPD mother and enabling, emotionally distant father. My desire to provide for my children a healthy and fulfilling life has really pushed me to work on myself. They have exposed those deep parts of myself, warts and all.
I think a lot of my guilt I have about my daughter is I helped put her in the very same hell I grew up with.
We can't stay sitting in that guilt-ridden state. It will be a disservice to your daughter. I know because I felt a lot of guilt with my d and the things she has seen in her short life. Guilt has led me to be over concerned about her in a codependent way, worry way too much and take responsibility for her bad choices. I think I felt I owed her that concern as a way to redeem myself of the guilt I was feeling. It's been hard to let her live her own life and make her own choices (and I have hated some of the choices she's made in the last 5 yrs). We are human. We make mistakes. We can't continue to pay for our mistakes by beating ourselves up over them.