Maybe I'm overanalyzing Mr Astley's incredibly deep and insightful lyrics but consider the following:
1. He'll give you up. He just will. Even if it's just because of his death and therefore loss of ability to assert conscious will. He will stop caring about you.
2. If he lets you down, it's really not about him. It's more that you placed unwarranted faith in him. In short, if he lets you down it's only because you were having him hold you too high up. So it's not really his choice to make of whether or not to let you down.
3. He has the choice of whether or not to run around and desert you. This he might actually NOT do.
4. As far as making you cry is concerned, he needs your permission to make you cry emotionally. You really do have to empower him with the ability to do that. On the other hand, he definitely has the ability to make you cry physically. Unless your one of those people who can't feel pain, he can bring some tears to your eyes eventually if he uses his pliers just right.
5. He really does have the ability to never say goodbye. I know I can't remember the last time I actually said goodbye to someone. I usually end with "see you later" in person and "bye bye" on the phone.
6. Finally there is almost no chance that if he talks to you long enough that he will not lie to you at some point. But you really do have to give him the chance to hurt you, much on the same principle from points 2 and 4.
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