There have been many pieces of advice for WSs that have struck me as quite sound...beyond of course the initial basics like full disclosure, etc. etc. The one that immediately came to mind when I saw your post heading was, "when you feel like running away, run toward". (I'm likely paraphrasing.)
So how can you do that, beyond not disconnecting yourself? Well, you've observed she's acting disconnected and cold, and that you're in the midst of A season. Have you broached that topic with her? How would it be if you were to acknowledge the season of the year and ask her how she'd doing with it, and how you might be able to help her get through it easier? If the first conversation gets nowhere, and you're still feeling the coolness (etc.), then bring it up again; note what you're observing.
HURT leads to withdrawal; when that hurt isn't noticed, and then the withdrawal isn't noticed either, the BS is left alone with all the bad and painful thoughts and memories and a sense that their FWS doesn't even care enough to see a difference.
Fear isn't going to help you or her, and you exceeded your allowance for selfishness with the whole A business, so it's time to wade into the water and see if you have a drowning swimmer who needs your help. Better to be hurt a little by the victim's flailing than stay dry on land and think "I should have done something" after they've slipped below the surface.