Relief: This is a general word for something that removes a burden or makes it easier to bear.
Benefit: Something that brings advantage or profit, the opposite of a burden.
Blessing: A good thing that brings happiness or well-being.
Gift: Something given freely and generously, the opposite of a responsibility.
Support: Help or assistance that makes a burden lighter.
Freedom: The state of being free from burdens or restrictions.
Ease: The state of being comfortable and relaxed, free from burdens.
Joy: A feeling of great happiness and pleasure, the opposite of the weight of a burden.
Lightness: A feeling of being free and unburdened.
Opportunity: A chance to do something good or beneficial, the opposite of an obligation.
Hope: A feeling of expectation and desire for a positive outcome, a sense of optimism that can help to lighten a burden.
Inspiration: Something that gives you new ideas and makes you feel motivated, which can help you overcome burdens.
Strength: The ability to cope with difficulties and challenges, which can help you carry a burden.
The best word to use depends on the specific context and the kind of burden you are referring to.