Not quite, with the braid.
Certain companies, BP included, were entitled to wear the "Executive Curl", as the loop on it is known, as a consequence, I believe, of war service losses.Clan Line was another, and this transferred to British and Commonwealth when Clan Line and Union Castle, amongst others, merged in 1955.
However, our braid was only 3/8" wide, as opposed to the RN braid, which is 1/2" wide. From a distance it looks very similar, which could be of use at some times when down in the Falklands, especially when I put my second stripe up on promotion to Third Engineer...
The RFA's braid is different again - they have the MN diamond, but used in the same way as the RN curl - in other words, above the gold rings. The normal MN braid has the diamond inside the rings.
Complicated? Not to us salty types!!
My dress uniform only comes out for matches, hatches and dispatches these days; in my present Company we do tend to only wear uniform in port. Normally polo shirts with the Company logo, but in certain ports we do go for white shirt and braid...
Lonely at sea? It's what you make of it, especially with mixed crews. Having t'interweb on board has made a difference though; sometimes you only see folk during working hours and at mealtimes. Dry ships has also changed social patterns, but in my Company we try to have a Sunday lunchtime social gathering with nibbles, but alcohol-free beer doesn't work quite the same as a couple of real coldies...