Living-hell [topic-は], exaggeration [quotative-だと] I [also-も] think.
生き地獄 (living hell) is a vivid compound: 生き (living) + 地獄 (hell, Buddhist concept). 言い過ぎ (exaggeration, literally 'over-saying') is a common noun. The sentence structure is simple — 私も思う with も indicating agreement with someone else's unstated view.