【Ghastly】 , 【grisly】 ,  【gruesome】 ,  【macabre】 ,  【grim】 ,  【lurid】  are comparable when they mean horrifying and repellent in appearance or aspect.

【Ghastly】 suggests the terrifying aspects of death or bloodshed. The term also is used as a strong intensive equivalent to hideous or horrifying.

【Grisly】  and  【gruesome】 imply an appearance that inspires shuddering or uncanny horror.

【Macabre】 may imply marked or excessive preoccupation with the horrors especially of death or it may come close to  【ghastly】 in its implication of a hideous or horrifying quality.

【Grim】 suggests a fierce and forbidding aspect.

【Lurid】  comes into comparison with  【ghastly】 as referring to light or color; it suggests either a 【ghastly】 pallor or coloring reminiscent of death or more frequently a sinister and murky glow. Sometimes  【lurid】  differs little from  【gruesome】 except, possibly, in its stronger suggestion of sensationalism.