Well, not sure. Have either of you had any std testing? Fewer sexual partners and exposures would obviously vastly decrease risk of giving and contracting an STD. This study addresses the idea of periods of time with a monogamous partner and the decrease in risk for std's. https://www.infectiousdiseaseadvisor.com/home/topics/sexually-transmitted-diseases/time-between-sexual-partnerships-associated-with-sti-risk/ It states "The risk of a sexually transmitted infection (STI) significantly decreases for serially monogamous individuals when the time between partners increases to longer than 4 months for women and longer than 6 months for men, according to a study published in JAMA Network Open."
My suggestion is to go ahead and get a clean bill of health for both of you and move forward together.