What does being pushy mean?

It means that the girl did something that he wasn't comfortable doing. If you text, call, or otherwise overwhelm him, he's probably feeling a bit suffocated. Also, if you ask him serious questions or where your relationship is going too soon, he's going to feel like he needs to produce answers just to make you happy instead of when he feels comfortable sharing his feelings. Just back off a bit and he will be a lot more likely to open up on his own time.

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Aggressively ambitious; overly assertive, bold or determined.