Good question. Ideally you shouldn't need to do anything to maintain a positive self image. Are you less of a person for wearing glasses, or needing a sweater in the winter? How about using a cast when you break a bone, or any other support device when appropriately needed? So why fret over needing diapers when dealing with incontinence?
In reality, society says we're somehow less of a person when we need diapers. So yeah, how do we deal with that. The ultimate answer is stop listening to others misinformed and misguided opinions. Easier said than done, I know. Really though, just keep doing everything you normally need to do. Don't let diapers get in the way of your life, and don't start hiding or skipping out of things for fear of being found out. Well, with the exception of swimming. Being submerged in water while diapered doesn't mix well. Everything else though, contine as normal, and eventually it will feel and be normal.
You'll also come to realize that 99% won't even notice. And 0.99% that do notice, don't care. And the remaining 0.001% that notice and take issue are really the ones with a problem. Pitty them, and move on knowing you're diapered behind is way more normal than they are. Also, don't treat your diapers like they are a top secret weirdo fetish that nobody should ever find out about. That only feeds into your own misgivings. Sure, treat them as a private matter that normally wouldn't be openly discussed with someone unless it's relavent. In a sense, they really are nothing more than your underwear after all.