Quoting: 7up
I am fear to change after marrige so I always refuse to get marry. Am I right???
Change is inevitable. It is the universal constant. You will change. He will change. You will both change, both as individuals and as a couple. Hopefully you will grow. The challenge in a marriage is growing together as opposed to growing apart. Successful marriages are based on growing together. If this is a man you can see yourself doing that with, your fears are unfounded. With all the love you already have between the two of you to build upon, I don't think you will grow apart.
If you haven't changed in ways that frighten you in the 6 years you've been together already, why project that you will in the future, just because you are married?
Are you two already 100% faithful to one another? Do you live together? Are you totally committed to one another? Is he your best friend, and are you his? What would change if you were married? Is there some aspect of either of your lives that you would not have if you are marred, and cannot live without? If so, it may be too soon. If not, what's the problem?