Hey developers!
So this post is mostly a solution to an issue you may encounter.
Problem: You are using a Mac device. You are creating a game with Unity. Everytime in the Unity project, you double click a script (or apparently an error/debug code), Monodevelop will open a new script window (instead of opening a new tab in a current script window you already have open).
Solution: Delete the .csproj files and the .sln file for your project
Link to a website that also details this: https://answers.unity.com/questions/1078859/unity-keeps-opening-new-instances-of-microsoft-vis.html
This really, really, really frustrated me today for the last 30 minutes or so, hope it helps others out there if they encounter this.