Dad Bailed On Rent- Left With $10k Bill

I rented an apartment in Cali with my father earlier this year. Our rent was about $2700.00 a month. In February I started working where I travel almost every week. I was home this year for only three weeks. I still paid my dad rent even when I was on the road but it was about $700 a month. HE NEVER PAID THE RENT! We got kicked out of the apartment and I got a bill for over $10,000 in back rent that we owed. Both of our names was on the lease but he never used the money I gave him to pay the rent. He has a bad drug problem. Now I am nervous this is going to ruin my credit because I do not have that kind of money to pay this debt that he created. He wont talk to me. I tried texting and emailing and calling and he ignores me. What can I do?