" highly conscientious "

Just doing what others wish is not conscientous in itself! It _may_ be depdending on situation but it can be just pathological towards the self.

When it's psyhocologically hard to do things you imagine will dissapoint someone that's probably not concientousness. It's more like low self-esteem or codependency.

It's very hard for someone to tell these apart themselves. Hence when this topic pops out it's good idea to remind that being super-accomodating may in fact be a personality flaw - that can be healed if acknowledged.

There is very large spectrum between "trying not to dissapoint anyone" and doing what you know is the right thing.

It's also a great opportunity for character development. Use it for that, and not for trying to overbook yourself to 300%.

You don't owe the world anything at all. If you're conscientious, then give a little -- here and there. Don't turn it into an unpaid job.