Roommate Moved Out 1 Month After Signing 12 Month Lease (colorado)

Location: Colorado

I own the house that I live in. My roommate renewed their 12 month lease last year. Within a few weeks, they decided to accept a new job and move away. Initially, we had positive conversations around the move. There was no lease break clause, but they understood and agreed that they would be responsible for continuing to pay rent until a suitable new tenant could be found. Despite these conversations, they slowly became more and more hostile. I actually started staying at my partner’s house because they were making me feel so uncomfortable. They texted me accusing me of creating unlivable conditions (among other things). I can prove that each of these accusations are false. They then messaged me saying I have to accept their move out or they will take me to court. I told them I had accepted they were moving out - from my perspective, I had never told them they couldn’t move out, I had simply made clear what their financial obligations would be regarding their move out. When I sent a letter to pay after they neglected to pay the last several month’s utilities and rent, they said they have in writing that I’ve accepted their move out - essentially they tried to manipulate me and use that as legal evidence that they had approval to move out. I would like to take them to court, but I’m unsure whether their manipulation might actually hold water. The fact is, they signed a lease. What, if any, recourse do I have here?