Yep - in my first playthrough without any clue how to play this I also ended in total fiasco, leaving 4 girls broken and in tears behind me
Did you ever use SanchoMod and Walkthrough? This is helping a lot to avoid dramatic breakups.
As Shitass recommended best way is to track only one target (solo or possible 2, 3 or 4some) and ignore all other girls so far possible. You have to plan your procedure strategically with Sanchos help
So I reached end of Chapter 4 actually with all 6 solo pathes, Heidi/Sadie and HAM without big drama and feeling a bad ass.
Now finishing on Heidi/Athena and MASH.