How do Christians react to adultery outside marriage ?

Generally Christians are against adultery as because people get hurt and trust is broken

 In the ten commandments, adultery is wrong "do not commit adultery", 

 Adultery breaks one of the vows when they have a marriage ceremony

Roman Catholic : believe that marriage is a holy relationship in the eyes of God and therefore adultery belongs within marriage, 

Other Christians including the evangelical Chrisitians  believe adultery is wrong as well as the Bible says so. They use passages in the New Testament like 2 Timothy 2:22 and Matthew 5:27 - 8

However, some Liberal Christians argue that adultery is acceptable as long as it is done as part of a loving relationship where no involved is harmed or exploited. They support this by saying Jesus' message was that love mattered most. 

The Church of England believes that marriage is God's gift to humanity and is the proper place for a sexual relationship and the best environment for bringing up children.

The Church of England recognises that there are different "family" relationship in today's society but regrets that an increasing number of people choosing to live together before marriage and some never marry, preferring cohabitation. 

The Anglican Church believes that chaning attitudes to sexual relationships have led to more family breakdowns and children have been hurt.