Is my lease a legal and binding contract?

As far as you are concerned, it is legal (unless there is something else wrong with it which you haven't mentioned).  The husband can authorize his wife (or anyone else) to sign on his behalf.  If she was authorized, the contract is valid.  If she was not authorized, the husband may (but probably doesn't) have the right to cancel the contract, as he would be the one whose rights were abridged, but you would not.  The husband probably does not have the right to cancel the lease, even if his wife was not actually authorized to sign on lhis behalf, because she would probably be considered to have what is known as "apparent authority", in other words, by allowing her to deal with the lease with you, the husband led you to believe that she was authorized to deal with it, and he can't now complain that she lacked authority.  If the husband is allowed to cancel the contract because his wife was not authorized to sign the lease for him, you can sue the wife for any damages you incur from the cancellation. I don't think that the fact that you were not in the husband's presence when the lease was signed is relevant.