I haven't finished episode 4 yet but I really think, thus far, we haven't focused nearly enough on Shu Yi ghosting…
I think you're forgetting.... Shu Yi and Shi de were in contact, they were busy tho so sometimes messages came late. Shu yi went to america to surprise Shi de and saw him with some american girl and a VERY new baby not knowing anything Shu yi thought Shi de was cheating on him so he went back he did not reply back to any of Shi des messages and then got drunk, broke his phone and gave it to his dad..... thats why they lost contact...