Five month sober is awesome!
If dieting is too much of a strain, just look at it as moderating your intake. Don't make weight lose your goal as much as making healthy choices and using portion control.
Observe how you approach food and when you find yourself overdoing it, back away. Drink more water to feel full. Add exercise to your routine. If you expend more calories than you take in, you will slowly lose weight.
The important thing...you are sober.