What an interesting question.
And you are a good person.
There are two things to judge good by: what we do and what our intentions are.
To me, intentions can be split into pro-social and anti-social. Like, my intentions are good if I intend to help others, and bad if I intend to hurt them.
Likewise, actions can be judged on their impacts - good actions do social good, and bad actions do social 'bad'.
Then it gets interesting.
If I rescue a puppy, that's a good action, in it's impacts. But, if I'm rescuing the puppy so I can torture it later, that's bad, because my intentions are bad.
If I kill Hitler, murder is bad, but my intentions are good. Killing Hitler prevents suffering, so, good action, good intentions?
But...
Stuff the ethics for a minute.
When I tell myself I'm not a bad person, I'm not trying to tell myself that on the basis of my actions and their effects.
I'm trying to tell myself that fundamentally, there is nothing "bad" about me. I am no badder than any other person, at the core. There is nothing outright bad, or dirty or shameful. Nothing that makes me more likely to act immorally than any other person. And the things that have happened to me, the things I did or they did to me, more accurately, they don't make me fundamentally bad either.
My innate "badness" is a core belief more than an evaluation of my actions or my intentions.
Because it's a feeling, not logic.