If by "ejecting" you mean that you wake yourself up, because you get scared, you can prepare yourself.

During day, pretend you just got lucid and something scary appears. Some people recommend to project love and understanding towards it. It's based on the premise, that it's a representation of some part of you that you don't like. Once you "accept it" by thinking "I love you" towards it, it will change into something non-threatening.

This has happend to me once in a lucid and a few times in a very vivid non-lucid.

Or, if you prefer to fight it, practice how you gonna defeat it. Raise a shield, throw some fireballs at it, pull out an RPG, make a rock fall on it... The options are unlimited.