Hey, JH1... peace to you!
Here's the thing:
From the WTBTS' most-oh-so-holy PIOUS perspective, it's not okay for a man and woman to be alone in a room. Prevalence of 'fornication' and all that. Yet, they have NO problem with a man and woman who, say, in front of and unbeknownst to 11,000 people (at a District Convention, perhaps?)... 'IN THE HEARTS'... undress each other and commit adultery... 'in their hearts'.
This is how it works:
You can be alone with a woman and have absolutely NO 'inappropriate' thoughts about her. Or... she can be 50,000 miles away, and you've 'taken her'... in your heart.
It is not that which we do PHYSICALLY that is so much an issue, as what we do in our hearts... and the MOTIVE and INTENT behind it. If you and this young woman have an understanding, then who is to judge what is in your hearts... IF you are both being honest with each other, and any other affected people, to the best of your ability.
IF your motive and intent, however, or hers, is other than what you tell each other... that's an entirely different thing. You're not being completely honest and perhaps even deceitful.
Let's say you're both honest, nothing's there between you, but that changes as you reside under the same roof. Again, it's a heart matter... did the change come due to the 'natural' progression of things, or did one of you intend for it to go that way, anyway, and manuevered and manipulated the entire matter to GET to that point?
As long as you two are honest with EACH OTHER... and any others 'significants' you might have in your life... residing under one roof is not a sin... nor does it necessarily LEAD to sin. It is what is in OUR hearts... our own DESIRES... that lead to sin... which is doing that which we KNOW... IN OUR HEARTS... is 'wrong'. Thus, we have been given a conscience to either accuse... or excuse... us.
And, even in the event we DO sin... we have a 'helper', the holy spirit from God, which helper can 'cleanse' us with its bath. But, one must recognize the uncleanness, acknowledge it, and ASK to be 'bathed'.
It is religion that condemns us, JH1, to pay the 'wage' of sin. My Father, however, by means of the blood of my Lord... holy spirit... grants us the FREE 'gift'... of everlasting life. We don't deserve it; we never did... and never can. We can, indeed, attempt to 'walk by spirit' and thus 'carry out no sin at all', but that has to do with our HEARTS... much more so than our flesh.
I hope this helps, JH1, and I remain...
Your servant and a slave of Christ,
SJ