Lorrym, I'm not sure what details you may have on the loss of your aunt aboard HMT Yin Ping. This was an Admiralty tug and appears to be among one of the last vessels to leave Singapore before the final surrender.
Checking through my copy of "Singapore Burning" by Colin Smith, he notes that there were 78 people on board and that the ship was attacked by a Japanese cruiser on 15 Feb 42, whilst trying to negotiate the Bangka Strait. Only 32 of those on board survived the attack. There is also mention of the sinking here:
About us
It seems, in common with many other casualties from around that time, your aunt may not have a known grave. Clicking on her name in the CWGC search record takes you to another page on that site. I include a link to the new page below:
CWGC - Casualty Details
From that, it would appear that she is commemorated within the Civilian War Dead Roll of Honour which is located near St George's Chapel in Westminster Abbey.
I'm sure that if you have any other query regarding your aunt, the CWGC would do their best to answer it.
I hope that helps a little.