Both of these poems are dramatic monologues which makes for a good comparison/contrast. The way that they are similar is that both speakers are aware that their love affair is about to end. The speaker in 'The Last Ride Together' is willing to accept this 'Why, all men stive and who succeeds?' However, the speaker in 'Porphria's Lover' is not so philosophical and kills his lover to try to preserve this perfect moment. He is aware that Porphyria has other men; 'vainer ties disserver' so he kills her in order to fully possess her; this is similar to 'My Last Duchess.' The speaker in 'The Last Ride Together' is willing to accept his fate and to take comfort in the memory of his love, whereas the other speaker takes action to avoid what may be his fate, without any real soul-searching.