You're halfway between Tredroy and Hadaton, a day's walk north of the river.
There's a north-south road a couple of hours east of you, which leads to a trading post on the river. You were heading for that road when you met Sasha; Hayu and the horsemen arrived from the east.
The river has a lot of traffic. If you can make it to the trading post, it should be easy to buy your way onto a ship. From there, you could go back upriver to Tredroy, or downstream to Hadaton.
From Hadaton, you could get a ship to anywhere.