Rotating the photo won't change the fact that those arrows don't line up. Whoever chopped the center seat bracing out weakened the frame in such a way that any force exerted on the rear wheel and through the rear shocks is folding the back half of the bike up and forward with the pivot point being where the swingarm meets the frame, just behind the engine.
In order to correct this, you could put a porta-power between the top of the rear shocks and the back of the frame neck, slowly force it back apart, take lots of careful measurements, and weld in some seat bracing to "finish the triangle" in the frame.
Another option could be to chop the rear and get a hardtail kit, if that's your thing, or maybe go the other direction and fab up a monoshock in that thing.