After a while of "doing it yourself", I think you get used to how you do it and any other way doesn't seem as good.
I guess there is two suggestions.
1) stop doing it youself. I know that sucks but, maybe that will make you more sensitive or needy for it after awhile
2) as someone else said, help you boy out by doing some of it yourself (aka touch urself down there while he is doing his thing