Hello and welcome! I read your post with particular interest because I too am not following a "diet" (and for me personally do not believe in them) but just eating healthful, mostly non-processed foods, with a lot of fresh fruit and veggies. I too think it is the most healthful and natural. I am also convinced our bodies process natural foods much more efficiently than all those chemicals, fake sugars, etc.
As for cooking, I have the same problem. I work long days and just plain hate to cook
BUT there are some great solutions! For one... by steaming veggies in the microwave I can cook an excellent, yummy dinner in just a few minutes. You can even get Ziploc steamer bags... just pop your veggies into them and stick in the microwave for a few minutes. Honestly I don't think cooking in the plastic is best but admit I do it, as my system is not perfect yet.

But you can also put a small amount of water in the bottom of a bowl and throw in your veggies. And corn on the cob just put it in for 4 minutes per ear, husks and all... then cut off the big end and your corn will pop right out with no silks on it even.
Also, there are a lot of item in the store which work... I buy cut-up fruit and also pre-cooked brown rice in little microwavable bowls. I do buy stuff like that and also spicy red canned beans... 1/2 can of those over the rice is a nice lunch.
Foil packets of tuna or salmon, etc., are also quick and easy!! I get the 3 oz ones, 100 calories each, which I keep in my desk at work for a quick, easy lunch.
Another idea is GoGo Squeez applesauce. Just pop off the cap and squeeze it into your mouth; easy to eat in the car.
There are a LOT of good options which don't involve a lot of cooking... even an old fashioned crockpot!! You just need to check things out and get a little creative!
I do it.. you can too! Go for it!!