The calculated distance (air line) between Sv. Ana v Slov. Goricah and Brežice is approximately 53 miles respectively 85 kilometers.
By car or train, the actual journey to Brežice is certainly longer, as only the direct route (as the crow flies) between Sv. Ana v Slov. Goricah and Brežice has been calculated here.
Air line (approximately)
85 kilometers
46 nautical miles