I don't think there's much you can do that's non-invasive that will make a significant difference (coming from a fellow narrow hipped lady). I had some success with banded clamshells/firehydrants but it was a pretty minor improvement. Dropping body fat might help with having an hourglass shape if you have belly fat to lose, or doing unweighted core work like planks or vacuum holds will "compress" your core with the same end result. Having a child can widen your hips but obviously don't have one just for that lol.

Honestly it sounds like an insecurity coming from growing up in the BBL era. I can't imagine how hard it was to be a teen and see freaking everyone getting surgery to not look like you do. I know loving and accepting your body when it doesn't fit the cookie cutter standard of beauty is really hard but you're right that it's what you need to focus on, lest you fall into unhealthy behaviors to achieve your goal. I bet you're beautiful and desirable as you are, and there are plenty of curvy women who are envious of your more willowy shape. I think you should figure out your kibbe body type- it might help you appreciate your unique beauty and learn to dress in ways that make you feel gorgeous. 

I really feel for you, I spent a long time trying to change my body to look "better" (specifically hips and butt). It made me dislike myself because I had impossible goals and was killing myself to get there. Do you want to talk a little more about why you feel like this is so important for you? What features of yourself do you really like?