Are you a second card holder on your DH credit card ?

I was reading in the Times yesterday that you are not covered by section 75 in certain circumstances on your credit card. Section 75 lets you claim agaist the card company if goods are defective and in other circumstances. However as the second card holder you are not covered if you buy goods solely for yourself . For example a girl's away holiday , a fur coat etc.. The main card holder must benefit from the purchase to be able to claim .
Also if you buy through a third party neither of you is covered. In this case it would be a holiday booked through a travel agent or goods bought through Paypal , Groupon and such like. Holidays should be covered by ABTA anyway but in some circumstances might not be.