Suicidal thought. To change his mind?

Both(girl nd boy)are close frnds for past 8months...He says that he loves that girl after 3months..., he got her love with the sentiment saying her that he can't live without her..The girl can't accept his sayings but with the fear of his talk she tried to make him understand but can't....That girl don't know whom to ask she adjusted herself to him thinking he might hv attempted suicide...with the thought after few days he will come to senses...but now the boy fixed his mind to marriage...c needs to marry him orelse he don't want his life itseems...He used to call  her daily cry and blabber sayng he is going to end his life..if she don't marry him...The girl don't want him to be her future Partner..she has family sentiments too..Now he has made his parents to speak to the girl and he is trying to move to the girl's parents too..The girl dont have a thought to marry him..What's the solution for the boy to change his mind?