I agree with the above post tell him that you prefer he tell you the truth (make sure he knows when you are told no you will not try to presure him into something he doesnt want to do) some times it is easier to tell you the white lie rather than deal with you pressuring them into going.... (which it sounds like you never would have done) I bet he has other friends who do thought!
good luck and be honest with your friend... and ask him to be honest with you in the future!
good luck and be honest with your friend... and ask him to be honest with you in the future!