I took classes specifically for learning to stand up for yourself (verbally (e.g. if someone hit you on the street that you would loudly and clearly, so others hear it and react, respond saying e.g. "You have just hit me. Do not do this again. If you do, I will call the police.") and physically (without touching another person, i.e. putting your feet flat on the ground to gain stability, straightening your back, lifting your head up and showing with your body posture that you mean it type of things) in public. This was specifically to help me with strengthening myself so I could learn effective ways to deal with assaults/abuse and to help me get help instantly and come across differently (not as a (possible) victim but as someone strong and not accepting of abuse). Those classes helped me a lot!
Some things on the path of recovery have made me (literally) only *feel* better, which was nice but didn't really change anything in my life (e.g. I would still be attacked in public by strangers and/or would just run for the hills in such a case), but these standing-up-for-yourself classes really changed something long-term, they gave me new options for taking action right there and then when an assault/attack happens and immediately afterwards. This in the longer term has helped me various times to stop abuse early-on and/or to get help and get me and my life back on track. Before having taken those classes (and before having really learned to act according to what I learned which needed some practice), I thought you couldn't do anything against others abusing/attacking/assaulting you and I was feeling very helpless with regard to getting help afterwards; after all, the abuse/attack/assault had already happened. These classes really helped.
As a teenager I took judo classes for a while. Those didn't help me at all with regard to trauma/self-confidence/PTSD. I find that "normal" self-defense classes (classes not specifically designed for self-defense in real-life situations) really do not help with dealing with things in real life. So, I would encourage people with traumatic experiences (abuse, assault) to look for classes specifically designed for dealing with every-day situations of abuse/assault.