You can break the lease simply by leaving. At that point, it will be up to the other person to keep paying if he wants to keep the property. If you both default, your businesses are both separately liable. Only the businesses can be sued unless you signed a personal guarantee which you believe you did not.
Not having read your lease and taking what you have said to be true, I believe that neither your personal assets nor your husband’s are at risk if you walk away from this lease. If you signed the lease with the other person as co-tenants, then the other person will be liable for the entire amount of the lease if you walk away. If you had a written agreement with that person, you may be liable to that person for not paying your agreed-upon portion of the rent. And, if that person fails to pay the rent, it is likely (depending on the wording of the lease), that the Landlord could come after you or the other person or both of you for the entire amount due. But, if you signed the lease in your capacity as an owner or shareholder, then the Landlord could come after that entity only and you will have no personal liability for unpaid rent. However, that assumes that you signed the lease on behalf of an entity like a corporation or limited liability company. If your business is simply a sole proprietorship that is not incorporated or registered as an LLC, you may be risking your personal assets (and those of your spouse). Whether your business creates any liability for you personally depends entirely on how you signed the lease, even without a personal guaranty.
I recommend that you take your lease to a local attorney for a complete review so that you can be fully apprised of your right and responsibilities under the lease. I wish you good luck.
This response does not create an attorney-client relationship and is not intended to provide legal advice for your specific situation