Re: 2 sims aren’t sleeping together

@simprolouge 
Thank you for posting. 
The bed - as you have stated - may indeed be blocked. A double bed would need to be away from the wall on both sides to have a clear path.
Sims are also prone to put things in strange places and not be able to move around them.
Be sure to check for books, plates, glasses and such.
You can also use two twin beds until you get the game sorted to allow them to sleep in the same bed. 
Marriage using the game options is a fairly simple solution. No huge ceremony is necessary.
Using game cheats is always a bit risky. 
Always save before using cheats like the one you suggested.  That will give the option to go back to before the cheat was used if something goes wrong.