Obviously I'm no master at dealing with shame as I've been trying to starve myself to death on and off for 28 years.
But..

One thing I do is kind of flip it....instead of viewing it as "I'm disgusting I let x happen" I try to tell myself " no. Despite all you've been through, you weren't gross or stupid. You were open hearted and trusting and loving.and those are GOOD things. Someone cruel took advantage of your goodness. That's not something to be ashamed of. Its like you painted a masterpiece and someone else decided to destroy it. You would obviously grieve the loss but you wouldn't blame yourself because someone was mean or crazy enough to destroy the painting.

I also view time as a river. The only moment that truly exist is where I am at this second. Everything else is already swept away somewhere I can't follow it, or is ahead where I can't see it. So when the shame is bad I.imagine those events receding down the river til they are put of sight.

I've also realized as I've gotten older that EVERY ONE has dark secrets. It helps to remember you are no better or worse than anyone else.