Need help with tenant troubles.

[Connor Lake]

Hi guys. I just purchased my first rental property and it already had a tenant in place. She is a very nice lady and always on time with her rent per previous owner. We just signed a lease agreement two days ago. When I gave her the agreement and rules for review she stated that she was a slow reader but she trusted me that the terms would be fair. I then told her that I didn't feel comfortable without her knowing all of the details so I asked if I could read the entire agreement to her and she accepted that offer. She agreed to the terms of the lease and the rules and regulations put in place.  When I went to the home today she was distraught and had her niece screaming at me because I would no longer let the tenant smoke in the house per the rules that she agreed to. The tenant claimed that although we reviewed the rules that she "wasn't thinking straight" when she signed the papers. I defused the situation with her and I told her that I would let her move out now and break her lease with no penalty if she did not agreed with the rules. She stated that she wanted to continue to live there. She just called me and said that she no longer wishes to live there if she can't smoke in the house but she doesn't know when she can move out due to financial reasons. I gave her the same option that we can break her lease and she will not owe me for the remainder so long as she moves out. She took that as her lease was void as of our conversation and she no longer owed me money but she could live in the house rent free. I clarified to her that the lease is still valid unless she has a definitive move out date. Does anybody have advice for me and how I should handle this?