I have heard a number of people claiming to be 'commitment phobic'. Reasons.
"I fear that I won't be loyal to you."
"I don't deserve you."
"For me career comes first, then a relationship."
"I'm too young. A harmless fling or flirting is ok."
"How can someone spend his or her life with one and only one person? Don't they get bored of eachother?"
"I hate the institution of marriage. Too binding. Maybe a live in?'
"Open relationship? Sounds like a better option."
"We are better off as friends."
But, when you are in deeply in love,
And done with your share of short term flings,
And when the feeling is mutual,
And when you dream long term - finances, marriage, kids, retirement...
Even at 19... Such excuses seem so lame and invalid!