How do you mamas do it?

I'm trying the "cry it out" method with my 6 month old and I feel horrible...I feel so guilty just listening to her cry for SO long (our apartment is so small so even in another room I hear her). How do you mamas get past it? What are some ways you got your baby to fall asleep quicker/easier? For mamas who have tried this how long did it take for your little one to get used to it? My heart is breaking and I feel like the worst mom.