You two may have started out on even ground, but over time it's become apparent that you're polarized in how you live your lives. You need a lot of security within a romantic relationship, much more than your partner needs. In fact, they need the opposite -- a lot of independence, freedom and space.
You have a hard time giving that to them; you might actually cling tighter the more they demand space, which can create a big rift between you. You seem controlling and rigid to them and they seem unreliable and unstable to you. It's not that these are fair or correct characterizations; it's just that that's the effect you have on each other, and those are the qualities that are exacerbated within each of you when you're together. When it starts to seem like either of you is not getting what you want, you naturally respond by insisting on it, instead of taking a softer approach. The interesting thing is, you stand to learn a lot from each other -- you know that's been the truth so far, and it could become even more real with just a little effort. There are aspects to each of your approaches that would be valuable if combined with the strengths of your partner, and it's up to you to figure out, together, what those aspects are. Once you do, you'll stand a much better chance of blending your strengths and presenting a united front to the world.