Ephesians 5:11 And have no fellowship with the unfruitful works of darkness, but rather expose them.
As we change in our relationship with Christ and grow closer to Him we will find that we want to spend less time with people who work against Him.
It is hard to turn your back on anyone when you know how special Christ is, but sometimes we do have to escape from the oppressive atmosphere that they carry round with themselves and come to praise God together with other loving Christians.
If they are secretly working against God and against Christians, then try showing others how it is damaging not just Christians, but society as well!