My landlord wants to break my lease to sell her house due to divorce. What does she have to do to legally break the lease? There are no clauses in the lease to cover if the landlord wants to break the lease for this or any other reason.

Buy you out. You have a valid lease and she can't terminate it without cause or your agreement. Nor does she have to. She can sell the property with your lease and the buyer has to honor it. Might make it harder to sell though.

Offer to move out if she will pay your apt search and moving costs.

She can of course always sell the property, but the new owner will have to honor the lease.If they want you out they will have to buy you out and/or work out some agreement you will agree with.