It doesn't mean you can't make room for them, Ayasha. I think it just means that you have to realize that in this area, they are not your primary support nor can you expect them to be a tool for strength. Whatever hardship your parents feel about other family members is on them not you. There is no question that if I had a family member that messed with my son, it isn't a hardship for me to know I wouldn't piss on them if they were on fire but hey, that's just me. So, with that said, I think you need to find a place where you are able to recite the facts of what transpired to them, with or without detail, and then let them fix themselves just like you are fixing yourself.
It is NOT your responsibility to make it ok for them, repair family relationships with a perpetrator, or make them understand how this has effected your life. I would, however, urge them to be in Therapy so that they can process and hopefully learn to be more supportive of your needs. Other than that, I think you have to keep your relationship with them on a need to know basis.
As well, since you know they are not your source of support, I also think that when you are having times where you are struggling, you should remain friendly but at a distance. I say that bc parents will say, "what's wrong" and that may find you in a weak moment where you try to discuss something that they will perceive as blame or intolerable which might put further strain.
At some point in time as you grow older, you will figure out the relationship you can have with your parents and it will be ok. First, you kind of have to learn your boundaries and what is ok for you to tolerate. I am sure they love you, but they lack the skills to be able to help you. Good, bad, or indifferent, they just do and they can't see past the blame they might perceive will be placed on them for what a perpetrator did to you. Selfish? Yes, but innate for many people but I believe in that saying, "when you know better, you do better."
In some stretch, your parents are ignorant to knowing how to deal with this and until they reach out to become educated, which you cannot force them to do by the way, they will never have the knowledge to set aside their needs and put yours first. It doesn't make them bad people. They aren't stupid. It doesn't mean they don't love you. They simply don't possess the ability to move beyond that emotion of blame. I know this because I have been guilty of it myself many times! This is the same need that I have to be RIGHT in an argument!
Hang in there and keep the faith! Know your parents love you but are not equipped to help you with this one! Forgive them and keep getting help from those who can and are equipped to help you. At the right time, you can give them the facts of what happened and then let them deal with it. Make sure YOU have a good support system in place when you do so and be prepared for them to have some anxiety. All you have to say is, "I love you and I wish I could help you understand but I have a hard time myself and that is why I see someone to help me through this. Perhaps you should do the same because I don't have the answers."
BIG, BIG (()) I really feel for you!