That's in her past, and was only once, though its not so distant past from the point before we met.

And she does posses most characteristics from my example list - "the person A". However I haven't seen her go into extremes since we're together. She did go out drinking recently, one time at occasion, and maybe few times in initial dating, but I don't know her friends, nor she knows mine. I don't feel the need to, though. Also, I'm not feeling possesive about it, but if at one point it goes to extremes, then I know from past experience, that girl is prone to risk things. For example, she mentioned not being able to find pleasure anymore in getting drunk at all, contradicting herself by doing it anyway in very rare instances.

One more thing - while some girls, lets call them "players", HAVE TO go out and party at young age (like its some kind of imperative, and because 'everyone' does, it must be "normal" ) like some dissipated men full of testosterone would, there are classy girls who never or rarely waste their time by loosing control, because quality women resonate with quality interests in their life. Former are under the complete influence of boorish western braindead zombie society. So that's another answer to the topic.

Now, in my case, we shall see what happens after honeymoon chemicals wear off, if then she goes back to something hidden in past, or begins to gradually increase that sort of needs.

But what to do if she maybe acted the substance and acted classy in initial stage to impress you, but shows typical female trait or two in time? I guess you monitor, but if she finally gives away some red flags, how to be clear about what to do when they come into play? (ie you can't prove cheating, though some of the flags are present, like hanging with female friend nights out that is a bit of a freak - ex drama?)

How do you know for sure that recent behaviour is consistent, if there appears, say, at least one sign from past behaviour?