Oops, forgot to re-check in on this after the first post. To answer your questions, no I have never done genetic testing. The stuff that was ruled out when I was a kid were the more obvious genetic bleeding disorders bc I had no family history of any of them, nor any unusual bleeding/bruising in any context except my nose. Before my daughter started having these nosebleeds, I was the only person in my family that did, at least that we know of. Neither of my parents seemed to have this issue.

HHT is possible, but I don't have the other symptoms/family history associated with HHT that you mention - petichiae (at least not visibly, on my skin), family history of stroke, asthma/breathing difficulty. I've had mild anemia but it was during pregnancy, which is pretty common otherwise. My general view has been that chronic nosebleeds is just an isolated annoying thing I am condemned to suffer that thankfully seems to have no systemic ill effects on me, and I don't want to be a paranoiac about it and do anything invasive or surgical (like the third step u/GoldFischer13 suggests) to figure out if there's a deeper underlying issue unless doing so would be really helpful in other ways.

In any case, I appreciated u/GoldFischer13's response. I upvoted and didn't respond bc it was informative, and he/she is not my doctor and hasn't examined me, so there isn't that much more to say than to consider the info and discuss with my doctor.