I would avoid the melon like the plague. Most diabetics can't tolerate melon, banana and grapes. Try the apple, have a small amount and test.
Take it from me, and believe me I know what I am talking about, you need to up your calories. Try to eat a minimum of 1,200 a day, if you eat lower than that, you are unlikely to be giving your body all the vitamins, minerals and nutrition it needs and you could end up very ill. When I was diagnosed as a T2 the Metformin had one hell of an appetite suppressant effect on me, and my calorie intake was tiny. If you are diagnosed as a T2 then it's for life, so you need to be looking for a diet that you can maintain, and that it will maintain you - for life!!
I am fine now and eat around 1,500 calories a day, often more, but I make sure I eat as wide a variety of foods as possible. I read up on vitamins to see which foods are rich in them. I eat nuts, seeds, oily fish, as well as a minimum of five fruits and veg a day, but most days I have 7-8+ a day. Restricting your calories will help you lose weight, but reduce them to low intentionally and you will be ill.