Be SURE BOTH low beam elements in the headlights are good..I had a 2004 Forester for 11 years. and heading home from upstate NY one night I LOST my low beams. Fogs didn't work either. Turned out BOTH low beam elements were burned out in the headlights. I didn't notice when 1 was out, but when both went, Nothing. Came home with high beams before diagnosing problem. On those Subaru's, the foglight relay is triggered by the low beam and when both were out, the relay didn't close.
Other thing that comes to mind is IIRC, there is a low beam fuse in the under hood fuse box. That may cause the same symptoms.
Just remembered this morning, at a later date, sometimes the low beams flickered when I was switching from High to Low with the light stalk. It eventually went bad and I had to replace the stalk. Another culprit to consider. Easy and inexpensive to replace.