I think people who either change their religion or FIND religion or ditch religion altogether, do so because they are searching for answers in their life which they haven't found in their exisitng lifestyle.

I met a Muslim the other day who was considering becoming a Buddist.

Basically the choice a person makes, whether to embrace a religion or discard ANY or ALL religion, has to do with a need to 'find oneself' (I don't really like that expression, but couldn't think of any other!)
and a way of life which one feels comfortable with.

Converting to another religion because of marrying into that religion is probably more to do with bringing up the children within that marriage. Easier if you are both reading from the same hymn book, as the say.

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