Could be thinking of the Chinese web novel often called 'Impossible Love Story' or maybe 'Love's Impossibility'? Pretty sure you're after the one by author Qing Luan. The main duo is Qin Zhiyou and Su Nian. Zhiyou's this cold, emotionally distant heir who builds walls around himself after past trauma, but Nian slowly dismantles them—she's persistent and warm-hearted in a way that doesn't feel naive.
The real tension comes from the supporting cast, though. There's Zhiyou's controlling mother, who's a classic antagonist but written with motivations that make sense. His business rival, Lin Chen, adds a decent love triangle element that actually drives the plot forward rather than just creating pointless drama. The story leans heavily on how these external forces make their connection feel, well, impossible.
I got a bit bored with the corporate takeover subplot in the middle chapters, but the characters kept me hooked. The ending felt earned, not just a magical fix.