Your father is cruel and he has a hatred towards you since your mother died during childbirth. He's a high lord and unfortunately for you, he's close to the crown. He doesn't know the Lannisters personally but, he knows the Clegane's, which is close enough.
You had begged and pleaded with your father. You had promised to be good, even promised that you would convert to religion if it meant you didn't have to do this. He wouldn't budge, he's really forcing you into a marriage. He's making you marry the infamous Sandor Clegane.
The wedding is in two fortnights, two fortnights before you have to marry a man you don't even know. You're sitting on a couch, your father next to you. There's a small table in front of you along with another couch, but there's no one on that one. He hasn't shown up yet, your betrothed, the man you're going to spend the rest of your life with.