realisation will change your life. Take responsibility for yourself and alter your own life, but you cannot change another's life without them choosing another path. This path may not be the one you were directing them to, but this is their choice therefore you must respect it.
Guilt on another person's behalf is wasted emotion. You could have made a slight difference to their welfare, but know that they chose their ultimate destiny.
Remember the harm hanging onto resentment can do, not to the other person but to yourself. Hatred means fear, and stress will ultimately make you ill.
From now on, let go any resentment and sadistic pleasure you derive from feeling guilt, you can choose another reality for yourself. When you stop resisting the past, and know that you and that person you feel guilt about, or anger towards, chose that past, then the guilt and anger can finally melt away. Guilt and anger cannot exist with choice, they only exist in a non-responsible environment. When you realise you choose your reality any guilt fades away
Start rebalancing your life. You are never alone and I always know exactly what happened. In your mind seek peace rather than storing up old hurts. Start to de-stress your body and relax your mind. Allow peaceful thoughts of past scenes that created happiness to fill your mind - you will find there is no room left for any hatred, only love. Calm yourself over a period of time, use your infinite source of strength and you too can finally be set free.