Hi there. I think you are on the right track in doing some research and coming on here. There really is no need to beat yourself up. You have been given the gift of being able to love. There is only good in that. How you go about loving so as to not hurt others but allow them to feel its wealth is the key. If they chose to avoid your love by leaving then that is their chose and is their loss.
I think that directing both here and telling them both that you would like to try poly out is a good way to start. Show them your thread and then wait to see what they say.
Good luck my friend. You are on the right track.