You're right, it's an inner game issue for you.

If you're not like this all the time or with other women, chances are you're just aware that you're a little more vulnerable to hurt because of what you feel for her. In short, the bitch down the street can't break your heart, but she potentially can.

All you need to do is recognize why you feel the way you do and decide how you want to handle it. That should depend on the nature and status of your relationship. If you're putting too much emphasis on the relationship when it's not really that serious, then you simply need to focus on your own inner game to resolve it.

If you're relationship is serious enough that you're considering life decisions, then she deserves to know what you're thinking and feeling. If she's worth making those decisions for and agrees with your assessment of the relationship, then she will actually be attracted to you more when you divulge the info, and become more fully satisfied with the relationship, which makes her less likely to act on the very things you're worried about.

If you put it out there and she backs away from it, then you'll know that you shouldn't be worried about the life decisions, and should enjoy the relationship for what it is today, and in doing so, you'll be less insecure because you'll be more conscious that if it ends someday, you'll be just fine and likely will end up with someone better anyways.

Good luck.