Hullo and welcome!
Your first task would be to look around and see what catches your interest. Maybe starting with what is polyamory and how it is different/similar to other forms of consensual non-monogamy. Getting to know the lingo can really open many doors, so check out the glossaries.
From how you've described your relationship, it seems you are mono looking to get involved in a vee with you as the secondary. So any of those might be a good tag search idea; mono/poly, vee, secondary/secondaries. Mono is a straight mono guy in a relationship with redpepper, who has been poly throughout the relationship. Check out his posts for ideas of what to expect.
Never fear, there is information and support available!
"Resentment destroys more alcoholics than anything else. From it stems the root of our spiritual disease."
"In dealing with resentments, we set them on paper - list people, institutions and principles with whom you are angry. Ask yourself why you are angry."
"In most cases it was found out that our self-esteem, our pocketbooks, our ambitions, our personal relationships, including sex, were hurt or threatened. We were sore, burnt-up." Alcoholics Anonymous, 64-65.