Welcome to OT!
I would try to save it, gifts do mean something for me and I would do almost everything to try to save them...
You probably had some sort of fungus growing in your substrate. Was the white "mold like" thing spread throughout the substrate?
When you write "careful with waterings", what do you mean?
Did you ensure that the media dried up even in the centre before watering?
What about the pot? ordinary clay or plastic, enough ventilation/drainage?
You saved it once and i bet you can do it again!