... in her own way, I think Mrs. Bennet is a "motherly" mother. When an outsider or even her own husband criticizes her children, she comes immediately to their defense, as I would expect any mother to do! ;-)

Even when she sends Jane to Netherfield in the pouring rain, I think she feels that the ultimate goal is so important that Jane must surely feel the same way too (or will, one day, when she is old enough to "know better").