For some teeth, I have to force it a little, my teeth are pretty close too. Its so worth it though: much better breath, clean feel, minimized risk of cavities.
I avoided purchasing one by forming a loop with the wire. I cut a 20cm (8in) piece, then I tie a triple knot (the simple over hand knot with both ends). The wire is very slippery so I move the first knot as close to the ends as possible, so as not to waste floss.
Having a loop allows to have a firm hold on the floss and adjust tension. I use it with both hands though. And I waste very little floss because I can rotate the loop and use every inch of it.
Thing is, teeth are so close to each other that literally nothing can get between them, not even food. I have however few teeth that get food in between, but these are the ones that already went bad and were fixed, and have gaps as a result of that.
For some teeth, I have to force it a little, my teeth are pretty close too. Its so worth it though: much better breath, clean feel, minimized risk of cavities.