Parents like optimism. We like believing in our kids, in bright futures - we're built for it.
But, beware thinking of recovery like a victory narrative. Eating disorder recovery isn't a battle you win and then credits roll. Successful treatment doesn't mean you're done.
This expectation we have that we will drag our child bodily out of their hell and get them cleaned up and healthy and then sit back to watch them go through life without looking back is the wrong script. The real story is that successful treatment is the beginning of leading a life that is consciously free of dieting, disordered eating habits, using the body as a self-improvement project, and seeing exercise as a payment for eating and a stress-relief drug.
Successful treatment is followed by relapse prevention: regular medical and psychiatric check-ups, strong emotional regulation skills, connection with friends and family, participation in society, useful work, and a good relationship with food and activity. The opposite of mental illness is robust mental HEALTH.
Sucessfully saving our children from a life of mental illness isn't a destination or a point in time it is a lifestyle. There are no credits, either - nor credit.
Most parents have this point at which they want to celebrate and "move on." Do celebrate (in private), and do move forward, but don't turn your back on ED or think he's like an enemy you've killed. The Hollywood ending you should be thinking of is the horror movie where in the last frame you see the hero doesn't see the monster is still breathing -- and you know there's a sequel in the making.