The law of survival in the Immortal World was extraordinarily brutal and only the strongest would survive. One must have a big background if one wanted to get ahead in that world, or could only resign to his fate.
It was rather fortunate that Tang Xiu had nothing left to lose when he left that world. Although he couldn't contact his followers and was unable to inform them that he was still alive, he still had his disciple, Gu Yan'er. She may be injured and her cultivation level had dropped to the point where she was like a new Immortal, but once she returned to the Immortal World, she would be able to restore her power at an extremely fast pace.
It must be noted that Gu Yan'er's cultivation had reached the Perfected Golden Immortal Stage before she came to Earth and nearly reached Supremacy Stage, yet she was still a force to be reckoned with there. No Supreme in the Immortal World could underestimate her power.