I had a severe ankle sprain 9 months ago. 2 months later began training for full marathon b4 completely healed. Finished, but now I can't even walk without pain and bruising. Is this normal? How long?

Have it re-evaluated. Ankle pain following and injury may last a long time. The pain may be due to a fracture, sprains, arthritis, or a soft tissue injury involving the tendon, ligaments or nerves . Have the foot evaluated so that you may get the appropriate care.
Ankle pain. Concerns include stress fracture and mechanical instability. Check with orthopedic surgeon for thorough exam ; imaging.
Ligament damage. You may have had significant ligament damage when you injured your ankle which became chronically weakened. I suggest an orthopedic evaluation for advice on how to prevent further damage.