I have taken gabapentin and xanax for 10+ years without problems. Xanax is a shorter acting benzodiazapine then librium. You may find you need less librium with gabapentin.
It needs to be monitored the interactions are:
Applies to: Librium (chlordiazepoxide), gabapentin
MONITOR: Central nervous system- and/or respiratory-depressant effects may be additively or synergistically increased in patients taking multiple drugs that cause these effects, especially in elderly or debilitated patients.
MANAGEMENT: During concomitant use of these drugs, patients should be monitored for potentially excessive or prolonged CNS and respiratory depression. Ambulatory patients should be counseled to avoid hazardous activities requiring mental alertness and motor coordination until they know how these agents affect them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities.
Hope the info helps? Be well & take care!