You’re right to be honest... Last season was riddled with these situations with the only difference in many games where a final minute or injury-time goal sorted out the issue.
Another thing I want to add is that Real Madrid have been showing a lot of anxiety on the pitch of late and that is one of the worst enemies for a side with lots of big name players. Instead of knowing who you are and playing to your strengths, you end up feeling anxious and attacking like mad leaving yourself open to counter attacks. This has happened a lot this season so far in many many games, even games where like at home to Valencia where Real Madrid didn’t exactly play a bad game, infact for me they were superior and won games where they played worse... What occured that night was anxiety in that Valencia were calculating on how Real would come at them and the players sense this. Similar things occured against Levante and as you pointed out, against Betis.