My nose has gotten progressively more crooked over the last several years. What are my options for correction? (photo)

Without an IN PERSON examination very hard to recommend anything. Sounds like you desire a cosmetic filler injection to give a straight appearance. This would not correct the "functional" issues ONLY to appearance. I would recommend surgery as a better option... 

Crooked nose with minimally invasive solution is filler to the right nasal bone depression. Or you could fracture the left nasal bone inward. I need to see photos for more info. 

The most minimally invasive technique regarding  straightening this nose will involve medial and lateral osteotomies and rasping the dorsal hump on each of the corners of the nasal bones. The procedure involves making an incision on the inside of the nose through closed rhinoplasty techniques under a  brief general anesthetic as an outpatient surgical procedure. A cast will be applied across the nose and left in place for one week and expect 10-14 days of bruising and swelling after the procedure. Also important to make sure there is no pre-existing deviated septum in the nose from the previous trauma. If so, this will be need to be fixed as well. For many examples, please see the link below