Without seeing a picture I'm not really sure this will work for you, but you can get curtain/drapery rods that extend especially far out from the wall. Using those should compensate for the unusual wall feature.
If you live in a hot/cold climate and were hoping to get some insulation factor from placing the curtains close enough to the windows to 'hug' the wall and thereby cut heat/cool loss, you can use a 'pelmet' style valance at the top of the rods to minimize the loss:
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