I honestly didn't realize for how many mother/son roleplay was a secret fantasy..
But just recently, a dear friend admitted to me that it was one of his as well.
That sparked me to do a little research into the subject on my own.
Clearly there is no reason for you to feel ashamed or uptight.
The numbers suggest that you are definitely not alone.
Yes it's taboo; very taboo.
But taboo isn't necessarily a bad thing .
That said , since it is a very different kind of role play, I've had to make some adjustments.
I 've decided that for a ninety minutes mother/son role play, what works for me is a consideration of 450.
For an hour, the consideration would be 350.
If that sort of role play is something you'd like to try, I hope it works for you too.