You have a big job of mentally reframing what is "good" food. I agree with the others that you will be able to have those foods again, in limited portions, but the bigger job is to start training your brain to love the healthy foods and start despising the unhealthy ones. Ice cream and simple carbs are the seducers that got you into trouble in the first place. You have to start thinking about them in term of what they actually do to your long term health. An exercise of CBT (Cognitive Behavioral Therapy) in overcoming addictive behaviors is to make a list of all the benefits of healthy foods (lower cholesterol, lower glucose levels, lower BP, weight loss, anti-oxidants, vitamins, etc) and a list of the bad things unhealthy foods will do (increased weight, BP, glucose, lipids, depression, loss of quality of life, higher rate of heart attack, cancer ,and stroke, decreased longevity, etc.) If you practice this daily, your brain really will start to "re-wire" to seek out a delicious food choice rather than a poor one, and you will have increased endorphin release by making the choice. Healthy choices are part of the lifestyle changes you agree to tackle when you agree to WLS. Don't obsess on the ice cream. You'll have it again, eventually. But use this first year to make the lifestyle changes and rewire your thought patterns so the sweets and treats will never take you down again.
PS: Another thought. Before surgery, I cannot count the number of times i would pray, "Please, God, I'll give up anything if You can just help me get this weight off." Then I had surgery and the weight came off. I am dead serious in saying that if I NEVER can have a bite of ice cream or sugar again, it is a sacrifice worth every single day of being a normal weight and having my life back. The fact is that you have to be willing to give up the junk if you want the health. You can't keep flirting with the food that made you fat in the first place. You can't have it both ways. Until you really hardwire the healthy habits and healthy food, don't put yourself in the way of temptation by entertaining thoughts of the junk food.