If you have been treated badly in the past, you don't have to grieve over that. For you can be freed, if you give up your life to God and Christ. You can namely then heal and get healing of emotional life, so that old and bad matters no more bother you.
However it requires a choice from you. You namely have to want to forgive and you have to give up all accusations towards others. For nobody of us is not only a victim, but we are also guilty. We therefore can not justify our bitterness or other our sins by that, that we have been treated badly sometimes earlier, because our attitude is quite wrong as our opponents' acts towards us.
So forgive and give up all accusations towards others, that you can get healing of emotional life!
Link: Give up accusations
may GBU!