The words “lose” and “loose” have the same vowel sound (and for some reason the extra “o” changes /z/ to /s/).
There are no other words ending in -ose that have the /u/ sound
Many words ending in -oose exist that have an /u/ sound, including the very common word, “choose”, which has the same /uz/ sound that “lose” has at the end
I never get these spellings mixed up but I can absolutely understand why someone would.