Meanings of emotionally constipated in English

Playing emotionally constipated characters, the actors improvise much of the dialogue.

If the Irish weren't so emotionally constipated, we would have hugged.

She was not just emotionally constipated in conversation, she was the same way in bed.

Bottled up until you become emotionally constipated?

I prefer his self-mockery to his self-promotion, as when he recounts his emotionally constipated relationship with demonstrative co-stars on a recent straight-to-DVD movie.