My spirit guide and I had it out many times over the power of forgiveness as I could not see how allowing someone that had done so much harm should be let off the hook. Letting them "off the hook" is exactly what we should do to free ourselves from the energetic (and sometimes karmic) ties we have created with our abusers.
Let's start with the basics. Energy vampires are usually lower vibrating individuals who feed off the life force energy of higher vibrating people. This is sometimes being done on a conscious level but often times it's unconscious. On a spiritual level, they are likely souls contracted to come here and force you (the empath) into learning to love yourself. After all, that is what most empaths are here to learn; love of self. I like to call them the teachers in the negative space.
No matter what has happened to you in your life, no matter how traumatic it may have been, know this: YOU DO MATTER. Your thoughts matter, your opinion matters, your dreams and wishes matter, your LIFE matters. Being victims of trauma can make us feel we are not worthy but this couldn't be farther from the truth. If you are feeling worthless, lost and completely alone, please know that this is not the reality of who you are. You do matter not only to many people in your immediate circle of human connections but also to the divine.