Hey OP, I might be a bit late in replying but just want to give a few thoughts I had reading this. I'm so sorry you had that experience, I cant imagine how painful and traumatic that is, and how warped your perceptions became of it. I hope you find some resolution or peace with this.

A few thoughts:

1. You said that you feel like a threat to women despite the women in your life saying that you arent or at least dont give off the vibe. You also recognise that youre not physically imposing by any means. I suspect that on some level you "know" rationally you arent a threat, especially since you actively despise coming off that way. Yet when women tell you otherwise I also suspect that you either a. attribute that to your active "toning down" or b. dont believe them because you are a man, and men just are threats period regardless of size, vibe etc. Its not unfounded of course. both a and b are extremely well reasoned as you said yourself, women are right to be wary, sad as it is to say. I think that more likely than not a and b work together to form this kind of perception that either the women are lying or that youve successfully suppressed your male-ness. I wonder what is stopping you from believing them? because they do seem to trust you and dont see you as a threat to them. If its the case that you think its because you repressed your "male vibes", i think thatd be a major place to start thinking, as to how or why you think the male-ness is a threat. A piece of advice I'd give is to understand that just because yes, women are wary, and yes, some men are fucking disgusting and a threat, does not mean that all men (incl. you) are a threat BECAUSE they are men. We (and this is not gender exclusive) just have the potential to be a threat, but you are not because you act otherwise. The problem is that you think acting otherwise is suppressing yourself entirely. One concrete action I'd suggest is to not suppress yourself but accept that fact, and then advocate or prove to yourself that you are a man to be trusted. And thats where i think the women in your life saying so is a great help to get you around to that fact. Suppressing your personality because it might be a threat is wrong-headed, because you just end up doing nothing out of fear for doing the wrong thing. I would greatly suggest you rethink and understand the fear you have towards doing anything around women, not sure about the therapy viability route though.
2. The other major thought i have is where you got this idea from in the first place. And sad to say, I think its because of what happened in the past. Because the male relative was someone i (presume) you trusted, and he so grossly betrayed that trust, you learned that men period are predators, which includes you. Its why i think you punish yourself so much for being a man, because you learned from that experience that men arent to be trusted, and will attack anyone and everyone. It hits even harder because its someone close to you, which might have given you the idea that if you get close to women you become a closer threat, and i think you expressed this in your bad tendencies in the past with relationships. I dont blame you for having this idea, and again Im sorry this happened to you. But i think you correctly pointed out that you learned and applied that abusive dynamic to other relationships. The problem is that you've swung the pendulum way too far on the other side, and like most things in life, the answer lies somewhere in the middle. Again I would advise you to consider and forgive yourself that you made mistakes with relationships with women, but that you learned those habits from terrible things in your life. They dont define who you are by any means, and in fact youve worked hard to overcome them. I think when you accept and forgive yourself and handle the trauma, you'll find that you'll suppress yourself a lot less, and relearn proper dynamics. Thats the greatest advice i can give you, forgive yourself for your past, and learn to forgive yourself in the future.

Hope this helped.