Ugg Boots! Conundrum With Sizing Of Uggs?

HELP! I’m a half size which is causing a problem. half a size down in Uggs feels extremely comfortable, pretty snug BUT loose in the heel. One and a half sizes down feels very tight, they are not comfortable at all, if I wore them with socks they’d be unbearably tight. What to go for? Do the tighter size really stretch enough? Is it just that the wool smooshes down flat or does the actual skin material actively stretch out too?