Should I ride my bicycle without a helmet?
You are the only one that can answer that question. By and for yourself.
I've been training Judo as a kid. Knowing how to fall has remained "ingrained" - I would have to make a conscious effort when falling in order to not tuck and roll, but to hit my head. In over 30 years of cycling and other sports, I've fallen countless times, never hitting my head. Ever.
Still, things happen. Beyond our control. Depending on the type of riding I do and my assessment of risks, I decide whether to use a helmet, or not. Most of the time I don't, but one occasion I often do are group rides - where riders are packed closely, so if one falls, the others behind are very likely to end up piled up - with other rider's bikes and bodies hitting you as you fall.
The other extreme is commute to work - on separate bike lanes at relatively low speeds. Wearing a helmet for that would be similar to wearing a helmet when walking. Or entering a bath tub - yes, people can slip, hit their head, it has happened. :)
Most other riding is somewhere in between the two noted extremes.
Another thing to consider is whether using a helmet will make you ride more recklessly - every choice has upsides and downsides. The only certain thing is: if you hit your head, you'd want to have helmet on it. :)