If I were to sum up the story so far then it'd be that shuuji was a manipulative asshole, the mc was someone with no backbone, and the heroine was genuinely dealt a shit hand such as living in a shit home environment and with having to pick between Shuuji and mc, she unfortunately had no choice to go with Shuuji because the mc (which would've been the healthier and better option for her) had no backbone or self confidence to voice his feelings for her.