millstone round one's neck

a millstone round one's neck (a thing or person acting as an encumbrance, a continuing difficult responsibility or problem) - ярмо на шее, камень на шее, непосильное бремя;

Who shall offend one of these little ones (children) which believe in me, it were better for him that a millstone were hanged about his neck, and that he were drowned in the depth of the sea' (Matthew, 18: 6). A millstone was a large, heavy, flat circular stone with a central hole; turned by the action of a water-wheel, sails, etc. at a mill, it was used to grind or crush grains

See also
[bane of one's life]
[нести свой крест]
[ярмо на шее ]

[гора с плеч]