import re

def repl(m, value, counter, NumberL):
    counter.i += 1
    if counter.i in NumberL:
        return value
    return m.group()

def replace(text,key,value,NumberL):
    counter = lambda x: None
    counter.i = 0
    return re.sub(rf"(?!\B\w){re.escape(key)}(?<!\w\B)", lambda m: repl(m, value, counter, NumberL), text)
    
text = 'Suddenly you said goodbye, even though I was passionately in love with you, I hope you stay lonely and live for a hundred years'
print(replace(text,'you','Cleis',[2,3]))