Will abuse happening now "cancel out" memories of an otherwise happy childhood?

Why do you ask?: Mental health / behavioral issues have more to do with how you process difficult / wrong life experiences than the experiences themselves. First and foremost, if you are in an abusive domestic situation, form a plan to get out safely. You don't have to tolerate this. If it's a work situation, you have rights under the law. Counsel from a therapist or other wise person can make all the difference.