How do i ask/talk my gf about this?

okay so heres the story.....when i was a freshman in high school i liked my best friend's sister, and she liked me alot but i was too chicken to ask her out cause i wasnt in the mind set of wanting to date anyone....i always saw her though, he would always have haunted houses that his dad was known for and i would be apart of it and i would always see her there and sit and talk with her and she has always liked me since then....im now a sophmore in college and she is a senior in high school and we recently started talking again after not talking for a couple of years cause of college. once we started talking again she instantly fell for me again and we started dating after hanging and talking for 2 weeks and we've been dating for almost 3 months now. ive had i think 5 girlfriends from freshman year of high school till freshman year of college and i have a hard time getting close with a girl cause i just felt like it was pointless cause it felt like it would just be another fling. all those relationship lasted a pretty good amount of time and i only one time told one of those girlfriends that i loved them and that took 7 months. i told jessy (my gf) that i loved her after 1 month because of how much i am happy with her and close with her, and after thinking for a couple of months of being with her, i kinda feel like i want this to become a more serious relationship, i wanna make it more serious without you know asking her to marry me cause thats way to fast for right now lol...shes 18 and im 20....i just somehow want to talk to her about making our relationship more serious without the option of getting engaged, i need another option to make it close so she knows i love her more than in anyone in the world and i might wanna be with her for the rest of my life cause this is like close to 7 years in the making of liking each other.How do i ask/talk my gf about this?
JUST GET HIM ALONE AND SAY WHAT YOU FEELHow do i ask/talk my gf about this?
First of all take an English class and maybe learn to type.

Then worry about the grown up stuff.
Maybe move in together. If thats too much maybe a promise ring. A promise ring just represents your promise to be faithful I believe.
look you shouldn't get married so soon...if you were my bf i would dump you because your way to desperate
Promise rings. Basically a promise that you want to spend the rest of your life with the person and want to SOMEDAY get married. A lot of people view it as an absitance thing. You can take it however you want though!! talk to her about it.
just tell her that you want to take the next level or the next step in your relationship..but make sure she is ready.
Don't make it such a big deal, and it won't be. In life, you have to learn to take risks. Sure, some girls will break your heart and some relationships will be dissapointments...But not all of them! Don't let something from the past affect your present. Learn from it, but certainly move on..She obviously likes you, and that's a pretty cute story. So just let things be, and be happy with your new relationship. It will gradually get more and more serious, but don't rush things...That's not your job, leave that up to time. Good luck! (: