I have been married to the same woman for 25 years. One and only marriage.
The best things you can do are all before getting married:
- Make sure the other person is sane, seems obvious but I have come to the conclusion it isn't
- Make sure the other person isn't a fixer-upper. Most (keyword most) people don't change and you can't change them, even if your last name is Freud.
- Make sure you agree on whether or not to have children (this is hard because people's desires do change)
- Make sure the two of you are sexually compatible. If she/he doles out Sex like its money in the great depression and you want it everyday you are going to have a bad time.
- Give your significant other space, don't be in their shit 24/7.
- Make sure you are your potential mates first priority. Are you really best friends, or are things just convenient? Do they choose others over you when given the choice?
- Be wary of people with extreme personalities. For example if you are marrying an independent loner type, be prepared to well, be alone with your thoughts. If you are marrying an extreme introvert, then be prepared for quiet. Once again this seems obvious, but so many people seem to believe people will change their stripes after marriage. Doesn't happen in my experience
- Lastly, stay away from people who are addicted to drugs, alcohol, gambling, or power. Your life will suck and your spouse will be the cause.
- If you aren't religious and your girl is (or vice versa) then you are going to have a bad time.
All in all understand this. Life is fucking short, marrying the wrong person is brutal. Time warps people. Bad generally goes to worse, good tends to great.
Understand this as well, good people do dumb things from time to time. You will have to forgive and forget.