Feeling like I would be able to let go of my RJ toward his ex if she got married

Does anyone else think this way? My RJ has been triggered around only one of my husband's exes - his most signficant relationship before ours. He was still sore about the breakup when we started dating, which is why I think she made such as impression on me (she left him for her brother's friend - my husband was also close friends with her brother and still is). She is also 6 years younger than me, I believe her to be more attractive than me, and she shares more in common with my husband in terms of hobbies. They have been broken up for 3+ years and she is still with the guy she left him for, but they have not taken next steps in their relationship. She was away for school for a couple years but is now living back in the same town as us.

I keep checking social media to see if she is engaged yet. I can't shake the feeling that if she got married I would finally feel secure about her. I get this feeling like my husband is such a great man, she must regret leaving him, therefore she must still be a threat. But if she got married I wouldn't feel this way. Of course RJ isn't logical, so there's no guarantee I really wouldn't feel this way. Kind of just wondering if anyone has similar thoughts or experiences?