Complex sentence: In the meantime, Gurney was gassed in September the same year and sent to the Edinburgh War Hospital where he met and fell in love with a VAD nurse, Annie Nelson Drummond, but the relationship later failed.
Split into simpler sentences: In the meantime, Gurney was gassed in September the same year. While at the hospital he met and fell in love with a VAD nurse, Annie Nelson Drummond, but the relationship later failed.