I like closeted narratives a lot, and wedding planners in love is a good avenue to explore this in, but I'm... not certain if the main character really jumped from unidentified attraction to knowing what this "it" is was the right move at the end. Also "haha lol idk why I told you I'm in a polycule" is not convincing to the reader. Be less convenient!!
Can't say this is great, more like 1.5 for me, the cheating is problematic as usual, but it is interesting that it pointedly asserts the polyamory. The best for the main character is to accept her attraction to women and move on from her love interest.