Complex sentence: Mitch asks why Dave did not invite him to his anniversary party, and Dave admits that he was embarrassed of him, but has grown to respect him while he was in his body and this allows Mitch to relax enough to be able to urinate.
Split into simpler sentences: Mitch asks why Dave did not invite him to his anniversary party, and Dave admits that he was embarrassed of him, but has grown to respect him while he was in his body. This allows Mitch to relax enough to be able to urinate.