I'm currently low carbing so restricting all carbohydrates to a slosh of milk in tea, a bit of FF plain yoghurt and non-starchy vegetables.
When I'm not low carbing, I still moderate my carb intake to maybe 1/4 cup dry volume of rice a couple of times a week or a couple of med size sliced new potatoes on a hotpot.
Once every few weeks I'll buy a sweet treat like GF chocolate & ginger cookies. I'll feel shit after eating them (physically... ie nauseous/headachy, not emotionally) and remind myself why I gave up sugar in the first place.
Re: fruit, I tend to just have berries, smushed into plain yoghurt. I eat apples in the Autumn, occasionally might buy an orange, but seldom. I think fruit is fine, with a few caveats... it is in its fresh, raw, whole state, ie not juiced, smoothified, dried, cooked etc. You want fruit that is fibrous. Fibre forms a matrix around the sugar, and that slows down the absorption of the fruit sugar to a level where the body can safely assimilate it. Any form of processing fruit (beyond roughly chopping it up) will destroy the mitigating effect of the fibre.
However, you don't have to go completely keto to get the benefits of a low sugar diet. Aim for whole foods and unprocessed ingredients. Look up the recipes of Sarah Wilson who is a great advocate of cooking without sugar.
The main thing is to cut out fructose, which is what is believed to be driving the metabolic disease/obesity epidemic. Apparently, no creature apart from hummingbirds can metabolise fructose on the fly... it is always converted into fat in the liver, which can lead to obesity and insulin resistance. Glucose in the form of starch is less bad, as long as it's eaten in moderation and in low GI type foods. So something like a grilled bit of meat on smushed cannellini beans & salad rather than a spaghetti mountain 