Welcome! I've just joined as well.
Once you know, once you FEEL that Love is infinite, and that by it giving to others, your partner isn't stealing any from you; once you discover that by giving it to others, YOU aren't stealing any from her, that's where you start to find the glory in polyamory. Wanting your loved one to be happy is a part of REAL Love, not the more famous cousin that wants SELF to be happy. (Well, wanting to be happy yourself is great, but as long as it's not totally selfish about it.)