hahah awesome question! i grew up with dutch and english abroad as well, so I guess I had a couple of years after moving back to holland that Dutch was a challenge..At that point I thought a lot more in English...But that shifted over the years..Dutch became the motherlanguage which I think in.

After moving back to german speaking and english speaking country...I all went very familiar, but Dutch stayed the main thinking language eventually! (although that sucks because dutch is a really ugly language hahahahah)