Amrit did say that her love will never end for him. If she does not want to go with Randheer, she should have clearly told him not to expect anything from her when he asked. That guy literally lost everything just be with that mad girl. He could have led a happy life if he were in Karachi as Sindh region was not that affected during partition. He lost four precious years of his life in some jail just to save that girl. He was humiliated publicly by her family, was paralyzed for 5 months just to save her useless brother Bhanu. And the biggest of all that thankless girl's parents died in his arms and gave him their daughter's responsibilities.
Lalaji's exact dialogues - " Amrit ka khayaal Rakhna"
To fulfill this last wish of LajRani he stayed back. He has seen Veer mistreating Amrit, then how can he leave her with him to lead this fake life. That girl can play with his life, put him hanging but Randheer after doing so much and going through so much can't even ask for his rights. I don't know about Veer as not interested but Randheer definitely is not a psycho. If a boy uses a girl and then leaves her then he is called different names, similar situation here Amrit used Randheer's love for her till now. If Randheer wants her back then how come he is termed as physcho