I am 99.9% it was in my drawer when I last saw it.
Several months ago, when she took her ring off and gave it to me I placed it with mine in the drawer. Then after a talk/argument about our MR she apparently went into my drawer and took the ring back without saying anything. I let that go.
The same drawer has letters she wrote to me while we were dating and newly weds. That too, after a talk/argument she went into that same drawer and took those letters (I so happen to find the letters in the trash can and got them back.. fortunately S8 did not do his chore of picking up trash..otherwise it would have been thrown out).
Perhaps you are correct that I should ask rather than accuse.