You do not lose your matrimonial home rights merely because your spouse is bankrupt.
However, what are these rights ? As far as you are concerned, it''s a right ( if not in occupation ) to return with the leave of the Court ( Family Law Act 1996 30(2)(b).
Your rights will terminate on Decree Absolute, although it is possible for the Court to extend these rights (though in your case I''d say this was unlikely for reasons which I will explain ).
Your practical problem is this : the trustee will, sooner or later, apply to the Court for an order for sale. For various technical reasons, it is not common for the trustee to apply until 12 months have elapsed since the bankruptcy. After that, however, it is extremely unlikely you could prevent it.
I have no practical experience at all with this situation but it seems that, at best, your moving back into the former FMH is, at best, a very short term solution only.