Tuning in to your knowledge of yourself, your ex, and your relationship is the best possible way to know how to interpret observed behavior. Think back about your relationship and how your ex communicates and deals with conflict. Is he blunt and straightforward? Then he's probably not hiding his feelings and you'll be able to tell if he misses you. Did he used to avoid you when he was mad and upset? Then his silence now probably means he's not pining for you — he's probably upset and angry and doesn't want to talk. Is he someone who lingers on things and dwells on the past? Then maybe he is thinking a lot about you. Use what you know about your ex and his personality to interpret his behavior toward you. Keep in mind that behavioral interpretations are filtered through the observers biases and wishes (when it's a personal relationship), and thus you tend to see things that are not actually there. If your ex is big on texting and you haven't heard a word from him since your breakup, don't try to interpret that silence to mean he misses you — he'd probably be texting you if he missed you. Try to look at his behavior from a more objective perspective. If your ex doesn’t miss you, she probably only contacts you if she really has to (for example, to arrange picking up her things from your house). If she does miss you, she will probably have a hard time resisting the urge to call, text, email, etc.  When your ex gets in touch with you, she may not have a specific reason. She might say something like, “Hey! I was just wondering how you’re doing.” An exception to this might be if your ex was the one that ended the relationship, but also expressed a desire to remain friends. If this is the case, getting in touch with you could be a sign that she misses you, but she may also simply be trying to stay friends. If your ex is constantly “drunk dialing” you, which means that she contacts you in the middle of the night after she's had a few drinks (and thus, is less inhibited) there is a pretty good chance that she has some...

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