But to me, up till now, the person who deserves me to give up my family to go with him in a completely strange country has not appeared. In the future, I can't say I will 100% sacrifice everything just for love, but 99% I won't sacrifice everything just for a man in the name of love.

A green card to some people means a lot, but to me, it is nonsense. I love my family, my nation, I like staying with them in my dear nation.

Love is a sweet thing to lovers, however, up till now, I have never  experienced this sweety feeling. To me, love means bitter and sorrow. Sometimes, I think I have never met my Mr.Right, that is why I never feel sweet in love.

Come back to your questions. Admittedly, there is indeed exist some people getting married just for a green card in the name of love, I don't want to condemn them, because that is their choice, their life, I don't have the right to judge them. You know, existence means reasonable.

I have witnessed how many people got married to the foreigners because they  really fell for each other and , fortunately, these couples are still together. I don't deny the existence of fictive marriages, however, majority of people get marry because of the affection. 

True love knows no boundaries. if two people really love each other then nothing matters for them. but fake marriage is also happening in the society which can't be ignored.

Is it the fastest way im not sure.

It can be for both love and green card.