As to how you look like, one may say accept yourself, but it depends on what the issue is, before one passes such comment.
When it comes to a healthy lifestyle, especially ” trying to loss weight and gaining weight “, you will need more work to make you look better and feel healthy.
Losing weight does not mean you do not love or accept yourself, when you are over weight, you should lose some to be healthy, it’s as simple as that. So as gaining a bit weight when you know you are underweight. Accepting yourself has nothing to do with not working on improving it.
Check your BMI often,get to know how healthy you are.