There is someone I see regularly.  Here is my dilemma! Sometimes she is tight and small down there, sometimes big and deep, sometimes short and wide, etc. etc ...

Is this my imagination, or indeed, the "gates of heaven" size varies depending on things?

I am the only she dates if that helps.

Maybe it's YOUR equipment that changes size from session to session.  Sedagive

When my girl gets a little loose down there, I just inflate her a little more.
Oh, wait, this is all together different. Nevermind me.

Well folks, thank you for your purely "scientific" answers!!! I know I should have asked this question in one of those medical bulletin boardS!  I am particularly shocked none of the providers gave any insight!!!

I think it may be a matter of excitement level and the amount of natural lubrication developed during foreplay.

Ok, sorry to be graphic (but you asked), but sometimes I can hardly insert a tampon on the last day because everything is so tight,closed and small.

And during sex, if I'm not sufficiently excited, it will be a bit hard to the guy to enter, and he will tell me that I feel "tight".

When I'm really hot, he slides in easily, LOL.

So, whenever I read reviews that says the woman was very tight and yet moaning loudly at the same time, I think to myself she must be a very good actress.

Thank you Gorgeous ... what you said seems to be in line with my experience ... but this brings up another question ...  when "it slides easily" ... would it make it more difficult for the lady to achieve orgasm?

I don't know that I notice any difference, other than sometimes it feels that I don't feel him as much, so I'll ask him if it feels tight enough for him just to be sure. This is when I happen to be just incredibly wet, or we are already on round two or three and maybe the playing has loosened it up..I dunno..But, it's always pretty tight and consistently so in the beginning - that doesn't change.
Different times during the cycle will change the PH balance and can cause wetness or dryness which will feel 'tighter' or 'looser' so that's a factor, perhaps.
I know there are plenty of ladies who continue to make dates during That Week, but I don't for several reasons, and one being the PH balance is 'off' for me making it drier and less enjoyable for starters. (And by the way, is it Murphy's Law or what that that's the week I ALWAYS get the most calls??? Never fails! Argh!)
Hope this helps.

Sedona

Just get her hot and wet!

If there's not enough lubrication, it is an uncomfortable feeling and it's hard to have an orgasm.

When a lady is hot and aroused, then the juices are flowing, you will slide in easily and it feels fabulous to her.....the next stop is orgasm.