Not sure what a proper term to describe this phenomena, but just what I realise about many people like to go for things that may hurt themselves or pull them to suffering. Knowing that person is not suit for you yet some people want to give in to everything because..I guess try their luck or think that love can change everything. Well, I do believe love can change many things but definitely not something that not meant to you. I guess this is kind of human nature about trying many potential thing even though there are risks that can be foreseen.
Little example from myself, I can really take spicy food but I still want to those super spicy food when it taste very good in the same time. It's very quite suffering to finish it yet I still want to keep eat it again and again. I not sure got out of topic but I can say that love is bittersweet while bitter is sometimes more than sweet, but people still can't get out of it and willing surrender to it no matter what.
I think if there is a scale or value for love, it's quite hard to measure and define a proper result for love. Love is really play larger part in most people's life because it's not just love of soulmate but more than that. It's lifetime lesson to learn and understand about love..I guess.