Self esteem and Dh is the issue here and clothes won’t fix that. I think I’d spend the money on a good counsellor to work on your confidence.
Agree that mners will help with the clothes so go and post some qs there.
agree that some exercise/ core work might help too.
re eating - start to do some simple swaps. You’re not aiming to loose weight but eat more healthy foods which will help belly fat and might also help mood.
From a sensory perspective, chewing is a very common de stressor. I work with children with send and the OTs often suggest crunchy food or even ice. Always apples. a teaching colleague needs to chew and uses chewing gum. The food industry has designed many foods to be sensory experiences which we crave more of.
I like crunch and will snack on almonds and cashews. And pumpkin seeds too. I adore chocolate so upped it to 70 and then 85 or even 90 to get that hit. (Cadburies is now too sweet.)
instead of crisps, rice cakes or oat cakes with some apple cider vinegar and olive oil.
Try to swap to more low fat protein with high fibre. Both are more filling and help gut bacteria. It’s also thought they can help mood as a result . More fibre helps to balance hormones which may be contributing to belly fat. Ground flax seeds, pumpkin seeds , oats, brown rice, nuts, beans are all really good sources of protein and fibre.
You won’t manage it all at once; just change the odd thing here and there and week you’ll find new habits. eg spend a day reaching for a few almonds and pumpkin seeds instead of what you know is shit. (Obviously not near anyone with allergies!)
(you can grind your own flax seeds in a coffee grinder which is much cheaper. X2 tbs a day is recommended. I put mine on porridge with yogurt. The bonus is that they make your skin nicer!)