Wonky, condolences on the loss of your husband.
The question of "need" can be a subjective one. If you're a firearms instructor and friends tell you that you "need" a revolver to demonstrate with, a .22 or .32 will permit that without hurting your hand. The difference between the LCR and the J-frame S&W with the same ammo is that the LCR comes with a cushier grip. You can get something similar from Pachmayr, Hogue, or Crimson Trace for your S&W .38.
If the perceived need is for defense, bear in mind that anything that hurts you in training may make you subconsciously hesitant with it in an actual emergency. If the Kahr and the Glock are fulfilling your concealed carry and home defense needs, where's the real reason to change?
Wishing you the best,