Is my diet healthy or too indulgent?

On a typical day I have porridge made with unsweetened soya milk and a banana for breakfast. Then for lunch I will have either a chicken or ham roll/whole-wheat sandwich without any spread, or sometimes I will have 4 whole-wheat crackers with a low fat blue cheese dairylea square - either way I always have some watercress and 4 cherry tomatoes with it. Then for my main meal I have some kind of tomato or roasted pepper or soy based whole-wheat pasta meal with chicken or bacon and plenty of vegetables, before I have a bowl of strawberries or raspberries (or some pineapple on Sundays) and a Muller rice. During the day I drink water, and have at the most 3 glasses of sugar free squash at night. The only times I ever indulge are on a Friday when my sister makes a Victoria Sandwich cake and I have a slice usually with the soy based pasta which is mostly vegetables like celery, red pepper, peas, broccoli etc. and also onion. I also exercise for at least 40 minutes each day just walking out in the country and do 150 sit-ups every morning. So my question is really does this sound healthy? I'm trying to ensure I can maintain a healthy, stable weight after just recovering from an eating disorder. Many thanks for advice/comments.