Regarding working out, you don't have to do a whole big "work out" to get things going. Simple walking on a daily basis is great. If you can do a good 30 minute walk most days a week, I think you may start to see things moving. When the time comes that you're comfortable going to the gym; whatever you choose, then go. Exercise is half the battle. If you don't move regularly, you won't be happy (as you aren't now) with the progress.
Regarding not being able to eat, you should talk with your doctor. If you feel weak because you can hardly eat, then you may be too tight. Being too tight will also slow your weight loss. Maybe it's time to check back in with the team at your bariatric facility.
I wish you the best.... Hang in there....you will find your way.