Professionally cooked western food also uses a lot of sugar and salt - especially frozen foods. Sugar is really fucking addictive so eating high sugar foods regularly will lower how much sweetness you'll get from it - this sounds especially relevant if you're directly adding sugar in addition to the sauce.
Sugar and salt both have very negative side effects if over consumed but a moderate amount of them is fine. I'd suggest trying to scale back the total sweetness to whatever level you can tolerate without it becoming bland and use more flavored spices to make up the difference. Additionally, not all sugars are created equal and it might benefit you to try switching off of refined sugar to one of the alternative sugars so that your body can more easily process your sweeteners.
Opinions may vary but I think it's incorrect to try to completely eliminate sweeteners from your diet, usually I've seen people suffer from extreme cravings that drive them to occasionally binge eat candy before returning to a "sugar free" lifestyle. It's important to respect yourself and allow for moderation rather than trying to cold turkey yourself. Duck sauce is extremely sweet but having a small quantity of meat smothered in duck sauce among an otherwise balanced meal can be a nice and reasonable treat.