Hi,
I have a friend that I have known since I was in primary school. I love her to bits, and would definitely count her as my 'best' friend.
The only problem is that she invites her husband to everything! I'm not wanting to never see him, I get along with him okay and we invite them out as a couple frequently. The problem is when I invite her to something as an individual, eg. A girly lunch, she will accept my invitation and then arrive with her husband in tow!
I feel awkward about saying anything as I don't want him feeling that I don't like him, I just really miss time with my friend as an individual. He can be quite controversial and dominant in conversation, so I find it more taxing to spend time with him.
Just today I invited her out for lunch...to be answered with "yes we would love to! But we will have to sit outside so we can bring the dogs" 
I genuinely don't know whether regular married couples come as a pair permanently or am I being unreasonable to want to see only her occasionally? As not to drip feed, my dh works unsociable hours so we hardly ever come as a couple, whereas they both work from home.