Actually these last few chapters reveal a lot and now it makes all sense why Ian always hesitates when he's with Jo. The way Ian didn't think twice to leave Jo and everything else for TJ says a lot.
Both Ian and TJ are still very much in love with each other. That's why whenever TJ comes with all his bad boi charms, Ian gives in easily.
They started parted ways when Ian wanted life and outgrew his mob environment. He wants life and future, but TJ wants power. Ian knew this and hoped TJ would change which is why he kept coming back to TJ, he fooled around with other men to get TJ's attention which didn't really work, until Jo arrived on the scene. Here's where there's major shifts in their relationship.
TJ is basically Ian's living wet sand. He just can't escape him by himself. That's where Jo comes in.
My guess is Jo will be Ian's end game as TJ can't seem to escape his own wet sand, the dark side of him.
Even in manhwa, sometimes you don't always end up with the one you love
Not sure I am understanding what’s going on but what I can say is that they always end up having sex instead of ACTUALLY wanting to fix things, these two are never gonna heal