Well that’s just because Doctor Who is a good writer. 
Dump her now. Not just because she is making you miserable, but because the longer you stay with her when you know you are unhappy and the more she invests in you during that time, the more she will resent you for wasting her time on a relationship when you know it isn’t something you want. She could be out meeting men that are perfect for her, taking classes, being happy by herself, and she is giving all of that up hoping that her relationship with you will heal and she can be with the man she loves. And on top of that, think of all you could be doing with yourself if you weren’t with her. Playing video games with your friends, learning to spell, etc.
Aw, shucks blush
For the OP, if you have a massive karmic debt…say you were a Nazi in a previous life, or encouraged the blasphemy that was Leonard “Spock” Nimoy singing Proud Mary, then you may as well marry the gal. Otherwise, not so much.
Spock, sure, but what about launching William Shatner’s musical career? Would that count?
Wow, thanks DooWahDiddy! I think I just blushed. All over!
There’s your problem. Them hermaphrodites sure are addictive, aren’t they?
excuse my poor english and writing skills, i am from italy and have poor communication skills in english.
There’s a certain kitsch value to what I call “William Shatner Music”, you know. Don’t make me use my copy of Common People or the Shatner version of Rocketman to demonstrate this! 
I must admit I was pleasantly surprised by Common People, partly from the irony of it.
Great Og Yedi!
You say you cannot stand her. You say that you are only 20 and obviously not ready to be engaged. She takes you from your friends. Did I mention you cannot stand her? It’s a no brainer my friend. Really. You are worried that you will hurt her if you dump her? Of course she will be hurt, but not hurt nearly as much than if you stay with her and both of you are fecking miserable for the rest of your lives.
Get out, move on, live your life, let her live hers. She’ll get over the hurt. Your lives will be the better for it.
Step one: Dumper
Step two: Give me her number (I like clingy girls)
Step three: ???
Step four: PROFIT!
Step zero: Dump her. Then dumper. Whatever that means…
Ponder how you’d feel if you were single.
Ponder how you felt with the woman before.
Ponder how you’d feel if you were still with this woman at age 50 and you had 3 kids.
You’re from Italy and you don’t have the guts to dump her?
That culture’s going to eat you alive, my friend. Move to Sweden or something.
which for some reason reminds me of:
[quote]
I’m no witch! I’m your WIFE!{/quote]
From your vernacular, I’m guessing your’e about 17.
Dump her and find someone else. At your age, nobody is worth that kind of grief.
How *you *doin’?
Well, that’s your first problem. Find a sharp knife, and cut those ropes. Then see if you can move away from her. If you can’t, then you might as well stay with her. If you can leave her, then say “Addio” and leave without looking back.
Assuming this is not a wind-up (even Italians know how to puncuate :eek: ), I suggest you do break up.
But you’re young, so do it gently.
Explain you’re not worthy of her. Tell her you’re not ready for a relationship, and you want to spend more time with your friends. (Actually that last one’s not very tactful, but there you go.)
I was engaged to my firsts husband when I was nineteen and we got married just a few months shy of my 20th birthday. At the time I was sure it’s what I wanted and that we would live “happily ever after”.
Now that I’m older and married for the third time let me assure you that you do not want to stay with this girl. And you most certainly don’t want to get married.
Break up with her and live your life. Get out there and do exciting things while you’re young and not tied down.