I would welcome her, let her know that you are glad she is there but that it's gonna be a little crowded - why not have her sleep on the couch? Is it too public an area? That way you could stay in your bed where the animals know where you are. She can stash stuff in your room, or any storage area (is there rentable storage space nearby if "stuff" is in the way) if necessary, though most people I know leaving abusive situations don't take much physical baggage, just plenty of the emotional kind. And, were I in her shoes, I'd feel AWFUL trying to sleep in YOUR room while you're stuck out on the couch.

I am glad, even knowing as little as I do of the situation, that you are willing to give her space and a chance to leave that situation now that she's got her courage up to do so.

How "temporary" is your grown son's stay with you?

Give the young woman a good, strong hug from me, though I don't know her, I've known others in her situation, sadly. She'll need all the hugs she can get for a while - and hey - doggie kisses count, too! Fur people are soooo nonjudgemental!