Hi,
 I am currently in a relationship. But after a long-time
relationship, he/she wants to break up. But she says she cares about
me. I love her but she says she wants a break up. She is a good girl
and understands everything. I don't want to force her in a relationship
in which she doesn't want to. Will it be ok to take a break to realize
our feelings towards us? What should I do? I love her so much..

Huribatas:
Be clear which one is you, a girl or a the boy,  who want to break up?
It  is obvious to be in love once you are in a  relationship, what kind of relationship emerge in your physical anatomy? Is it a love that you want a long term relation or a youth physical attraction and be proud be around girls or boys and feel energetic?
If you are thinking of long-term relationship, a marriage and spend rest of the life together, you must have an understanding between both of you, you both should be able to keep personal issues away rest of the life, must be derived by mutual interest, some common hobbies and so on.
You did not mention how long you have been in relationship and is this relationship is just seeing each other or much more, like staying together and sharing beds.
Find out the reasons of the decision of breaking up? May be she/he was not interested in long term relation other than physical? May be he / she did not see common goal to move on?

My clear view is once you get married try to keep it of life but if you see it is not working now may not work in long run, better not to ruin your and his/her life , living daily unfriendly environment. It may turn into hell, living in same house and sleeping in different bed, cooking your own food. No one should go through the hassle of  divorce and if you have children , pay alimony until the child reaches at the age of 17-18, she/he may enjoy civil marriage life but you still be paying alimony rest of you life.

Think and come with logic, if you do not see it working , even trying,  let it go and move on, you may not able to forget it but there is saying once you start seeing other the old one starts fading but may not be wiped out completely.  I could not come with real nice Nepali proverb and I came with it , which may seem vulgar, please suggest me to replace with your nice one " जहाँ नसो पस्यो त्यहा माया बस्यो " . 
Button line do not drag the relationship, it should be smooth and must have mutual interest and understanding, some sacrifice and some dedication, if you lack these right now, may not be come in future. Move on.