goldy...I guess I missed it but, where is the question in your post? Or maybe you are just wondering, is it normal to go from LD to HD seemingly overnight?
I can make a statement about that from my history, if it helps. When I was married before, it seemed that I was the LD spouse and my ex-h was the HD spouse. But after a divorce, a new husband, and a lot of reflection, I think now that I was actually always HD, I just didn't have lust or desire to have sex with my ex-h. For a while I thought that my getting older (I am about your age) was also contributing to my HD, and that could be true, and of course I figured the fact that I am extremely attracted to my current H and getting all my needs met also contribute to my HD. But when I really examine the truth, I know that I was always HD, I just didn't want to have sex with my ex-h.
Why? Well...there were numerous reasons...sexual attraction was never there (he was the classic nice guy and it turned me off), he wasn't meeting my needs as a husband (I had to do everything, literally everything...medical, kids, financial, major purchases, major decisions, housework, yard work, I was the main breadwinner, everything you can think of in terms of leading a family, including all the involvement with his very large family)...his sexual aptitude was very low...it was just plain all around a dud of a sex life for me. For his part, he felt that all that was needed to have sex was an erection, and since he had one, we should have been getting it on. No matter how I would try to entice him into taking on a bit more in our marriage, some new things in the bedroom, etc...it never seemed to make any difference. I realize now, he is who he is and I should have just loved him for who he was, or left much earlier.
Anyway...so for many years I wondered where the heck my sex drive was...I had remembered having one before being married...where did it go? I was physically attracted to my ex-h and therefore, I wondered why I didn't feel like having sex with him? I think now that I was too naive to understand that physical attraction can be present and still be lacking sexual attraction (and even vice versa).
Soo...I can definitely relate to suddenly feeling your full rush of HD coming on after leaving your H, if your sitch was anything like mine. My ex-h didn't repulse me, per se, I never felt that about him. And once we did get going on sex, I enjoyed it. But I never felt my blood boiling over the way I do now.