The pilot reported that he was inbound to his unlit private grass strip at night. He sat in the right seat and maneuvered the airplane to land on runway 17. He reported a slight crosswind from the left. When the airplane touched down on the up sloping runway, it bounced once and then settled onto the runway. The passenger heard a "crunch" sound when the landing gear hit a bump in the runway. The airplane veered to the right and the pilot was unable to maintain the runway centerline. The airplane continued to the right and impacted a barbed wire fence about 115 feet from the runway. The left main landing gear separated from the airplane and the right wing sustained substantial damage. The left brake line was found separated. The pilot reported that there was no forward visibility in this airplane during ground operations. He also stated that his failure to maintain control of the airplane contributed to the outcome. Based on the evidence, it is likely that the pilot did not maintain directional control while landing on the unlit grass strip at night with no forward visibility.