Paruresis is nothing to feel guilty about. If you would like to share on here why you feel guilty then i can assure you that nobody will judge you in a negative light. The thing is with this condition is that whatever has brought it on, many men on here will have developed paruresis for the same reason so you are not alone.
I wouldn't say paruresis is hereditary so don't waste time worrying you will pass it on to your boys. They will be so used to using public toilets naturally either at school with friends or at public conveniences with their friends and each other that they will be used to urinating around adults and at that age won't think anything of it.
As Andrew suggests, read posts on this message board, post messages for support and we will get back to you, and book yourself on a workshop. There will be one before Christmas and trust me the workshops are very good.