I was GPU mining 2 bitcoins a day on good days in late 2011 with a bitcoin price around 2$ @ 2 gh/s @1200watts of power at a comfortable profit loss. I'm glad I just kept those coins and didn't only look at the short term profits when deciding to continue. What helped was living within my means, a long term vision, and having reserve capital for expenses during lean times.
And a little bit of luck, you must admit. Things could have gone the other way just as easily. Happily, they didn't, but with any venture luck always has something to do with it. I'm just getting into all this now, so I look at your situation like I'm hoping someone will at mine in 2019.
Maybe but it was mostly having a good macro understanding of what I was dealing with despite it being a trollfest in here with horrible daily news, laughing something awful members trolling and hacking the forum and proclamations everywhere that bitcoin was dying or dead and going to pennies a piece. I was buying when the blood was in the streets.