I have been dating my girlfriend for about a year and a half. I love this girl do death and have always done as much as I could for her. She is a very nice and beautiful girl. Just some things irritate me and that I can't keep dealing with it, and when I bring these matters up to her she ignores me and walks off like she doesn't even want to talk about it, so basically I can't express how I feel what she's doing that annoys me. Also the fact she seems to always have to find something to get mad at me, even the slightest things no one should even get mad about, I just don't understand sometimes. The first year and 2 months have been amazing but these last few are just miserable. Then this girl I have known before I started dating this girl I had liked a lot before, she is much more outgoing and fun to talk to and easy to talk to as well. Even till now I still like this girl, that I realize it, even though I put it in the back of my head the whole time to focus on my relationship, now that I'm a little unhappy in the current one, she's been coming up in my mind. The only thing with her is she lives about half hour away from me by car, and her family is a little controlling with her and schooling so they limit her time of hanging out a lot that's the only downfall with it all.
I know I would be happy with this girl very much, but then I thought the same with this one which I was right for most of the time but now I'm second guessing it. What do I do? I can't tell her to go on break because then she would just make everything final and that will be it, and I don't want to end it but yet she expects a lot out of me and doesn't appreciate enough what I do for her it seems like. Were only 18, I'm responsible, mature and everything and do want to settle down, but I don't know if this is what I want, we argue almost every 3-4 days because she has t find a reason now, she's starting to slowly pick my friends, what I can and cannot do and now she's taking away my most beloved hobby, basketball. Its like everything has to revolve around her now, were only 18 and everyone says don't get serious yet and I'm starting to feel that I shouldn't this fast yet, because I feel its getting out of hand what do I do?

If you're not happy and the two of you can't communicate you should consider breaking up.
It seems you're going around in circles and the antagonism is escalating.
Sort out your present relationship,that's where you're at at the moment and don't overthink past relationships.

Reality is setting in, and as with ALL relationships, once the "honeymoon" is over, you start learning a lot of things that you didn't know before, and some of them you don't necessarily like.

Its up to you if they are deal breakers, or not, but fair warning, leaving one girl for another, and skipping the healing part, is a disaster that will bite you in the butt.

If you cannot talk to your g/f, and work things out, leave her alone, and do your thing, and don't be fooled into going after someone else.

You must learn to be single, and happy with yourself, before you share it with another, or else you have misery, hurt, and confusion to offer, and that's not fair, to yourself, and others.

Its up to you.

Your age doesn't have anything to do with it. 2 of my friends have just gotten married and both are just 18 years old. I will be getting married on the brink of 20. This has to do with maturity, commitment, and your knowledge about how to handle a relationship, and how to make it work.

You need to realize a few things. Firstly, that feelings for other women while you are in a relationship is completely normal. You aren't a crazy sick person, for wondering what else is out there, or even checking out a couple girls in the mall. Normal boyfriends, girlfriends, husbands and wives will sneak a little peek, or question their current partner in comparison to all the other's out there. In a relationship, this isn't at all unusual.

-(Acting on these feelings, including flirting, or physical contact is wrong when you are in a relationship. You cannot escape the temptation to cheat. This is why it is important to put limits on your relationships with girls that aren't your girlfriend- and you should tell your girlfriend if you don't feel comfortable with her being physical in any way with other men... It's not control- it's protecting each other from being tempted to cheat. Setting up healthy boundaries like this could save a relationship.)

So, if it's normal for past feelings, or random feelings for another woman to pop up in the middle of a relationship, how do people stay together? Relationships will last, when they are not based on the feeling of love. When you are drawn to this other woman, while you are dating someone else- you need to CHOOSE to love the person you are with. Love is a choice to be commited- it's not a warm, fuzzy, feeling. Studies show that the emotional high of being "in love" wears off around 2 years into a relationship. If your relationship is based on feelings, it's not going to last when the feelings wear off. You need to CHOOSE. If you aren't willing to be committed to your current girlfriend, whether you "feel" loved or not, you need to let her know that you want a break, or a break-up, because it wouldn't be fair for you to stick around.
Many, many relationships end in ruins because the couple can only survive if they are both feeling loved. The truth is, when you both CHOOSE to love each other- that is where true love deepens in a relationship. You need to decide if you are committed, or not, and go from there.