Hey UP Ashley,
Welcome to our forum.
We technically call your kind of dynamic a "triad" (or even "delta/triangle"). Threesome tends to speak more of the phenomenon where three people have sex together. Not that the labels matter. As you've found, every triad is different, and very few triads are perfectly balanced.
Make sure you do a lot of high-quality communication with each other. Set a date once a week or once a month, depending on how much drama you're dealing with, to sit down and talk to each other, share feelings, update each other on what's up in each of your minds and hearts, etc.
Hopefully, Polyamory.com can help you with the bumps along the way.
Glad you could join us.
Love means never having to say, "Put down that meat cleaver!"