A SERM crashing libidio immediately brings to mind a "simulated" estro-crash. When you are using ralox you're preventing E2 from doing all of its normal functions, including acting in the brain to promote sexual desire and arousal. Every person has their own receptors so what might be debilitating for you may not affect someone else.

My rats have have displayed similar libido issues with SERMS in a very dose dependent fashion.
I.E.
> 20mg of Tamox = infrequent weak rat boners
10mg of Tamox = frequent massive rat boners