I'm so sorry this is worrying you so much.
You will only transmit herpes to your child if you have inappropriate sexual contact with them.
Herpes doesn't shed from the buttocks - the skin is too thick there. It also doesn't transmit from objects like toilet seats - everyone would have it, if that were true - or from casual household contact.
Herpes requires sexual activity to spread - direct skin to skin contact. In the case of genital herpes, you'd need to have unclothed, genital to genital or genital to anal contact with someone else, usually in the form of intercourse.
I know it's scary when it comes to our kids, but you don't have anything to worry about. :)