how to commit to marriage/long term relationship?

popcicle girl

hey there everybody, i have a question that i don't know if it can be answered but here goes anyway.
i am engaged for over a year now and my fiancee says this is the year we are GOING to get married.
by the end of this year he wants me to be his wife!
i am scared to death of this!

i have been married before but that has nothing to do with the growing gnawing fear in my stomach when
i think of this as being forever.
how does one commit to FOREVER?

the concept of it just amazes me! yes i love him very very much and i know there SHOUJLD be no doubts
but the doubts do not lye within my love for him but within the concept of forever!!!

does that make sense to anyone? sometimes i think about something just being a week away like a concert or something that,
and that seems like an eternity to me, or his birthday coming up in march and the surprise i have planned for him i know he will love!

those times seem so far away let alone a life time with someone!
when we fight once in a while i wonder how on earth can i spend a life time with this guy but then of course we make up and i wonder
how can i spend a life time WITHOUT this guy?

do you see the delima that i am in? not really in but the questions that i go through in my mind?
any advice from long married people on here?