I want to start wearing diapers again
I hope you are joking. Why do you want to wear diapers?
Because sitting on a dirty diaper is really comfortable
It's understandable that you have a need for comfort. However, you should not allow yourself to carry on with wearing a diaper if you are not in need of one. Instead, you should find something suitable like a soft blanket to bring you comfort.
But I want to pee in it, I get the most comfort when I am wearing a dirty diaper. This makes me feel warm and loved.
Usually adult do not use diapers unless they have a medical issue. You should be glad you do not require them and not want to use them.