One of the things I love about language is its ability to grow and evolve with the societies that it inhabits. Even the biblical definitions you cite have been translated and re-translated from cultures that are very foreign to ours. That's what interpretation is for. It's how we find the way to attach ideas to words in ways that are relevant and can be understood in the context of the society that uses them. So for me, it's only natural that definitions for things such as envy and jealousy evolve to be more relevant to the people that use them
For me, I can't apply the definitions you use to polyamory because I don't view another person or their love as something that I lay claim to or something that is rightfully mine. For me, love falls under the category of grace. Grace is neither deserved, nor rightfully belong to anyone. It's simply there to be appreciated and treasured. The love I have for a partner, or receive from a partner, is not a possession for me to hold, but a grace for me to appreciate every day.