To add, I am not a believer in 'soul mates' - I believe your compatibility with any person you meet can be measured and there are some people you're more compatible with than others. I think a relationship or marriage can work in different ways, there is more than one version of a 'happy marriage' for any individual.
My marriage works, I think, because we have similar tastes in a lot of things - the way we like to spend our time, entertainment, music, holidays, TV and films. Not entirely identical tastes but there is a large overlap. In other areas we are different - we don't often agree on politics, for example.
In some ways, we have learned to put up with each other - I have accepted, for example, that he is a chronic faffer and will never change, whereas I am the opposite. He puts up with me being quite a messy person around the house.
Importantly, we share a sense of humour, we can have each other in stitches over things others might not think particularly funny - we have several 'running jokes' in our marriage.
Essentially, we look after each other, enjoy the time we spend together, and put up with each other's faults.