Oh please, don't over do the dramatics. She wasn't betrayed by the MC and neither by Andres.
She sure does a piss poor job as parent if she can't deal with a moody 13y old kid, then sends him to his step dad, cause apparently Andres can deal with him and the MC blames him on ruining the relationship with his mother and cheating on her on top of that...
In the first place Andres being the bio dad or not, isn't even important, he was who raised the MC, what does it matter if he is not the sperm donator ?