I rewrote it real quickly just changing around commas mostly. Note - there are plenty of other ways to write this to improve the flow, and make it sound better if it were spoken. Mostly I just kept it as close to the original as possible.
My brother came back yesterday, I can't believe he is right here....
You've been away for more than five years, I missed you so much.... Mom convinced you to go to (CollegeNameHere/CollegeNameHere University/College in LocationNameHere - Saying 'that college' is gramatically dubious) I heard our parents talking about it, it was my fault...
Mom told you I was getting too attached to you. She said that it was in my best interest to put some distance between us, to let me learn to be more independent and help me get over my crush on you. But I still feel the same away about you... nothing has changed for me. After dad died you were the closest thing to a father I had left. You look like him, you sound like him, and you were so sweet and kind to me.
When I was sad you were there to comfort me. When I was scared you were tehre to protect me. When I was feeling down, you made me feel beautiful. You used to brag about how cute your little sister was, and you would get jealous when some guy tried to talk to me. You made me feel treasured. You cared for me and made me feel wanted.
Just looking at you is so soothing. You're just like dad, but closer to me, and within my reach. I want to make you mine. I want to do my best to make you happy... to make you fall for me.
I dreamt about this day, it felt like an eternity. But the wait is over and you're right here.... My dear brother is back, my beloved is back. This time I won't let you go away. I know you want me too. I know you only agreed to leave because you wanted what's best for me.
This time I will speak my mind. I will be honest with you and myself. I won't be afraid. I will do anything I can to be with you. I will fight for you. I will stand against the world if I have to, my sweet brother. This time I will not lose you, I wil give my all to you... You had my first kiss and you will have all my firsts. I know you were holding back before, and I know you didn't try to go further because you wanted to protect me. You didn't want to take advantage of me, but I want you, as much as you want me. Maybe even more.
Sometimes you can really be a knuckle head. I was so sad when you left. It felt like I was losing you forever. I felt so lonely without you. Everyday I came home hoping to see you. I used to wake up at night calling your name. Thank you so much for coming back. If you didn't come back soon, I was ready to go find you. I would follow you anywhere to be with you. I swear I won't let anything stand in our path. I will protect our feelings, this time we will be together. I will show you that I welcome your love. I will make you fall, even more, for me... I love you... I will prove it to you. I will make you mine.