Why is love so cold but we keep finding ourselves coming back to it?

I have had several girls I've always loved. One of them was the first one I had a decent relationship with. I kept building up trust and faith with her and then her parents closed down our friendship. I knew we had something special, I loved her so much. We've never talked for over a year. Another girl I liked I thought I'd have a fresh start with to help me get over my first bad experience. She was great looking, we had similar interests in music and a lot of things, and we always wanted to talk to eachother. Then I told her how I felt about her, she said that she loved me too but like a brother. In other words just another way to say no. We still talk but I can't stand being near her. My heart always longs for her. Currently I like a girl who randomly Facebook messaged me the day before school, we talked. Turns out we had 2nd class together. We talked a lot during first semester, then after that we didn't have a class together although a teacher would open up the class walls and shed want me to sneak over and sit by her. I usually did. Then right now it's summer and we've not seen eachother since the last day. My parents go ape s*** the second they see me talking to a girl. They either confront me in front of the person or tell me afterwards not to talk to them. They never understand. Anyways, yesterday the girl told me she loved me and I told her I loved her too. Texted her that night and no response. Again this morning no response. Is she playing hard to get or is she turned off somehow? I mean I'm a really nice guy and I've stood up to one of the girls boyfriends for abusing her and put him in his place. I'm not bad looking, I'm muscular and everything, but it just seems like something is keeping me away from them. Idk. I need 2 things in life to stop me from going insane, someone to love, and someone to look up to. I don't have someone to love because my parents maybe will divorce. I have god and everytime I look up to him i find comfort. But I need to love to