Is “because you let us” a valid reason why I ask why people always disrespect me and treat me like crap?

All my life,I’ve been at easy target for bullying and being picked on. I’ve been yelled at, beat up and treated like a dog because I’m autistic. When I was a cousin a couple of my cousins used to make my life a living hell. it’s been happening for very long time until the parents and my dad found out and they called them out big time. Then they told me that I needed to stop letting them push me around and start standing up for myself and be more firm. The adults were like “Poor thing getting pushed around” when I was a kid. Now as an adult they told me I need to stop being a coward, be a woman and stand up for myself. Some of my cousins still pick on me and push me around and the worse thing is, I let them. I could complain constantly but I get scolded at for not doing anything about it and it’s my own fault. My male twin cousins said something to me and yelled at me in my face last year. My late dad got fed up with me. He got in my face and said, “Why do you let men talk to you that way. Quit being so weak!” He wasn’t not afraid to call it as he sees it.
Then he hissed and said, “You’re being very WEAK!!” And kept getting into my face. He was aggravated that I let them disrespect me. He never said I was weak when I was a child.
One day I demanded my cousins “That’s it! I can’t take it anymore! All my life I’ve been called weak, a coward and pushed around. You guys bullied me and you continue to treat me like crap. Why do you keep doing this?” One said, “(Scoffed) Because you let us.” And walked off. Another said, “She’s right. YOU let us treat you that way. We thought I know you would stand up for you but you keep letting you treat you like that. We guess what you love being treated like crap and don’t have the guts to have a backbone so we kept doing it to you and most of the time purposely to see if you would say something.”
Then another said, “You’re a coward and a pushover. When the hell are you going to stand up for yourself? You’re easy and I don’t mean it in a good way and too nice. You let us do it and it’s your fault.”
Sorry that this is long but I can’t believe they would say that to me. Do you think they’re wrong or right?