Whatever the excuse but CR has a contract with the club and he was paid very well for it as well. If the club demanded him to stay last summer and play as a sub then he shall take it as a pro. For all the talks about his love for United and its fans, his action doesn't look like one, not even a bit.
Also this is something for CR7 backers to keep in mind, anyone who try to publicly badmouthing their employer the way Cristiano did, will be fired in no time and might actually found harsher treatment as well. Whether the critics are the truth or not is another matter but you just don't go public with such matters.
It is up to the manager, ETH to decide who to start and bench. CR was paid to play for United and shall act like one. Sadly it has came to this. Good riddance but now i am not sure what to do with my Ronaldo 7 jersey.