With so many electronic devices using radio signals, and many others (such as printers and even central heating switches) emitting radio frequency interference, any receiving device has to be able to separate out the data it's looking for from the background 'mush'. Some devices have far better 'selectivity' than others, so they'll be able to process wifi data far more quickly than others.
The wifi adapter in your OH's laptop, for example, appears to have far better sensitivity than the one in yours does. However that might only apply to the particular channel which your router is currently using. If you change the channel you might get different results. (If you need instructions for doing so, please tell us the make and model of your router).
It might also be interesting to see if you get different results using another speed-checker. This is the most popular one
http://www.speedtest.net
but, as long as your phone line is actually owned by BT OpenReach (rather than say, using a Virgin Media cable) then, irrespective of which ISP you're with, here's the 'official' one:
http://speedtest.btwholesale.com
It would also be interesting see what speeds you each achieve with a laptop connected to your router via an Ethernet cable. You ought then to get the same speeds. (i.e. it's the wifi part of your connections that's slowing performance, not anything along your phone line).