"not evidence that she consented to sex with the accused"
No but it might provide support to a psychological analysis of why she might decide to falsely accuse the last one.
"consented to sex with the accused on Thursday is usually not admissible if the accusation is assault on Friday"
Probably fair but how about "have you had sex with your alleged attacker more than 1,000 times and in each of those times if you changed your mind part way through the act did he ever force himself on you?" seems completely relevant.