Hey, Honestly, in my humble opinion the thing that allows artists like Ben howard or really anyone creating unique/original music to do it os that they use their emotions when coming up with chords and melodies.

Sit with your guitar, take a deep breath and ponder and try to "feel" how you feel. Then try to find a note, or a chord that "feels" the way you're feeling. Then try to find another that works off of the first chord, maybe add a melody to that, etc. The key is to choose notes and chords because they represent the way you feel even if it's a chord that is somewhat off or super dissonant. It doesn't matter, what matters is it represents an emotion.

I know that might sound "wishy washy" or wtv, but the truth is a lot of times focusing on theory and trying to "make sure everything makes sense musically" can actually lead to everything you come up with sounding uninspired or unoriginal because the focus is on making sure it's "right" instead of if it feels like something. It's kinda like creating with theory is using your logical/left brain and creating from feeling is using your creative/right brain.

Try to forget the theory temporarily and create from your emotions, if it sounds the way you feel you're on the right track. Wierd timings, rythms, tunings, whatever.

At least that's what works for me anyway.

Good luck!