Lt Cdr Roope's Victoria Cross for actions when he was commanding the HMS Glowworm says this;
The enemy broke off the action and headed North, to lead the Glowworm on to his supporting forces. The Commanding Officer, whilst correctly appreciating the intentions of the enemy, at once gave chase. The German heavy cruiser, Admiral Hipper, was sighted closing the Glowworm at high speed and an enemy report was sent which was received by H.M.S. Renown. Because of the heavy sea, the Glowworm could not shadow the enemy and the Commanding Officer therefore decided to attack with torpedoes and then to close in order to inflict as much damage as possible.
It seems to me like if he recognised that he was being led towards a superior force, it was quite reckless to continue to engage the enemy, especially since it ended in the loss of his ship - but I'm completely naive about naval tactics.
Clearly he was an extremely brave man, but why was he rewarded for deliberately engaging a ship he was outmatched by, when it sounds avoidable?
Partly, the citation is written with the benefit of hindsight - we know now that the German destroyers Glowworm first encountered did have back-up, but for all Roope knew, he was being bluffed. The destroyers might have been pretending they had support, in order to force Roope to break off the combat. He also knew that part of his job was to locate strong enemy forces, to report their location to his own supporting forces, and to shadow them until help could arrive. Breaking off contact could have been seen as a dereliction of duty. Following the German destroyers allowed him to fulfil both parts of these - to discover if the Germans did have heavy supporting forces, and to locate them for his supporting ships (Before breaking contact to search for a man overboard, Glowworm had been operating in company with the battlecruiser Renown). Note that he sent a contact report to Renown, in the hope that she would be able to engage Hipper. However, due to the bad weather, he was unable to fulfil the third part of the scouting role. Glowworm had ended up at close range with Hipper, couldn't easily open the range, and had to remain within the range of Hipper's guns to shadow, due to the poor weather. Thus he felt that his only choice was to stand and fight, and do as much damage as possible, in the hope that this would allow Renown to catch and sink Hipper, or even sink Hipper himself.