I am a 16 year old male. I have known this girl since grade school. We have both liked each other since then, although we didn't tell each other the first three years. A few months ago I asked her out. She comes from a Christian family, as do I. We don't argue much, but from what I have heard a little arguing is healthy. She and I have been through so much that we both agree if most people went through what we did, they would hate each other. But something always draws us back to each other no matter how bad the situation. I can never ignore her or stay away from her, and she feels the same. We keep getting drawn back to each other.
More about our relationship: We both have agreed to stay away from sex until marriage. If we touch one another's areas we do stop (pants stay on). We are both growing in God and I believe she is helping me a lot with this.
But recently, I've had a "voice" in my head telling me to dump her. I do not do it because I don't see why God would want us apart and because I'm thinking it could be Satan trying to tear us apart. I know I am young and that I don't know much about true love, but she is an amazing young woman. I do believe I am in love, or falling in love, with her. And when I say "love" it's not that "mushy butterfly" feeling I get; I'm saying I want to help her grow in God, I want to protect her, and I want to help her make good decisions in her life. My main question is: How can I tell if this is God or demons and Satan?
Personally, I wonder why people reach for exotic answers instead of asking why they are having self-doubts. But in answer to your question, you put your question to the test, just as you should do anything else. "Beloved, do not believe every spirit, but test the spirits, whether they are of God; because many false prophets have gone out into the world" (I John 4:1).
One of the tests John tells us to use is whether this is making us more worldly or more godly. "They are of the world. Therefore they speak as of the world, and the world hears them. We are of God. He who knows God hears us; he who is not of God does not hear us. By this we know the spirit of truth and the spirit of error" (I John 4:5-6). From what you have said, this relationship is more based on God.
If I had to guess, I would say that more likely there are some doubts because you two have drawn together at a young age and there are questions whether you are missing out on something by not seeing what else is available. You aren't really missing out on anything, but as you mentioned your lack of experience makes it difficult to tell.
You two still have several years to go before you can get married. Don't be in rush to make a firm commitment yet. Allow things to grow between you at its own pace. "I charge you, O daughters of Jerusalem, by the gazelles or by the does of the field, do not stir up nor awaken love until it pleases" (Song of Solomon 2:7).
You mention that you stop if you touch each other's private areas. I congratulate you on your restraint, but I want you to be a bit more proactive -- don't even allow yourselves to touch those areas. I don't want your resistance to be worn down. Go out of your way to protect her honor, even from you. In every situation think about how this might look to someone who doesn't know you and your commitment to God. Don't give Satan even the smallest crack of an opening.