[verb ます-stem] + づらい
づらい means "hard to do" from the point of view of the person doing it: the action is uncomfortable, awkward or painful for them. It goes on the ます-stem of a verb – 歩き, 言い, 食べ – and the result is an い-adjective. It comes from つらい, "painful", and is written in kana.
The thing that is hard to deal with becomes the subject, so it takes は or が where the plain verb had を: 本当のことを言う becomes 本当のことが言いづらい.
づらい changes like any い-adjective: づらくない, づらかった, づらくて.