We should just start crossing things off the "if ______ happens, that will be telling" list:

If Tom attends EO's sister's wedding - didn't happen
If EO attends Tom's sister's wedding - didn't happen
If they spend the holidays together - didn't happen
If she flies out to Oz - didn't happen
If they spend Tom's birthday together - didn't happen
If they spend Valentine's Day together - not looking like it
If they spend her birthday together - doubt this as well
If they spend the break together - they didn't spend the last break together so I'm calling this highly unlikely as well

I think whatever was going on ended in November when she flew out to Hawaii.