You have titiled your question "risk". I might re-title it "trust". I hope I can help to provide you with a bit more confidence that you are not at risk. The bottom line here is that you cannot get HIV from someone who does not have HIV and your partner does not have HIV. Rapid tests for HIV are just as accurate as the more widely used (because they are cheaper) blood tests sent to laboratories. If she had HIV, even if she were taking the medications for HIV, her blood test would remain positive. You can believe the test results. Currently available tests give entirely reliable results within 6-8 weeks following exposure.
A few more comments only partially related to your question. You seem not to believe your partner's statements about when she last had sex with her prior partner, whether or not she has HIV, etc. Perhaps there are other reasons for these thoughts.
Hope this helps. EWH
On a more general level, from my perspective it really makes little sense for you to be asking about your risk on a partner-by-partner basis - far too much emoptional energy is expended this way. Ask you partners about their status, use condoms, and get screened for STDs periodically (more often if you change partners more often). You are already doing most of this so keep it up. If you cannot keep from worrying each time you and a new partner choose to have sex, you should do more, such as adopt regular condom use. EWH
If there are more questions you will have to ask another questions however, if the question is yet another anxiety-fueled, paranoid expression of your angst, it will be deleted without comment.
If you cannot get by these most unlikely, unfounded concerns, you should seek the assistance of a counselor or other mental health professional who can help you to work through things. I say this out of concern and in all sincerity. EWH