Hi Cali and welcome. I don't think you should wait to tell your son about your suicide attempt...he's going to hear it from someone and better it be you who tells him.
Your Aunt is ignorant..(I don't mean that in a mean way) she just isn't imformed so she used the throw away line..."a selfish act".....it's like telling someone that suicide is a permanent solution to a temporary problem.
There are many ways to approach this subject with kids....ex: my depression almost overcame me but I'm so glad I'm alive.,, my brain wasn't thinking right...I almost made a bad choice...etc.
And it can open up a diaglogue...."you'd tell me if you ever felt this way...right?"
I've been amazed by some of the things my grandkids have told me about their suicide discussions at school with their friends. KIds talk and it's best they have the right information.
Did I say welcome to Neuro Talk? *grin