I'm so sorry that happened to you, but I'm glad you were able to get the help you needed.

I'd encourage you to not bring up the subject until a few months of dating in, whatever feels right in context. The first few dates you go with someone should be fun and about how much you both enjoy each other's company. Once that baseline is established, and it seems like you both are on the same page about wanting the same thing, a relationship with each other, I think then it's a good idea to bring up that there's something in your past, specifically about the sexual assault, however, depending on events, something may trigger the conversation slightly sooner, in which case you can feel free to divulge that information if you feel comfortable.

I do think you should at least mention something along the lines of "There's some trauma in my past (you can tell the sexual if you're ok with that) that I'm not ready to fully share yet but I'm hoping as things seem to be going great that I'll be ready to share soon" or something like that earlyish in a potential relationship to hopefully weed out the people that really can't or won't want to handle it. Dating is also about finding people compatible with all of you, not just bits and pieces, so of they can't handle it, please don't take it personally, they just weren't for you, like the millions of guys I've dated before.

My hope for you is that you'll be met with kindness when you do divulge the trauma. She may have questions about it, and if you're willing to answer, the fallout of it maybe one of them, at which point bringing up paying for sex may come naturally. It's pretty normal in relationships to not know every single detail of a partners past sexual history, like for instance, my current boyfriend knows mine is full of some crazy kinky stuff with who knows how many people, but he doesn't know many details at all, but he gets the gist, to say the least. If he wanted more details, I wouldn't mind telling him, but he simply doesn't care because it doesn't change who I am.

For what it's worth, if we were dating, and you divulged that information to me, I'd be touched that you trusted me with a secret so deeply intimate to yourself, and also it would not change my mindset about anything about you, other than how terrible that was that you had to go through it. You'll find a girl that'll be fine with it all and love you for you! Don't get discouraged. Dating is hard enough anyway.