Marriage is a huge step in a relationship. If you are in the right relationship and it is the right step, it will be a new beginning for you both. If it is the wrong step, then there are good chances it will lead to separation, then divorce, finding another partner that you are compatible with, and remarrying. If at first you don't succeed, there's a good possibility you will repeat the cycle many times. Each time you get divorced, the possibility of getting divorced again increases.
There are many ways that help you know if your girlfriend is the one you will marry.
The test of time is a good indication as to whether or not you should marry her. Have you both been together for a long time? If you've only known her for a short period of time - say six months - its likely marriage is not the right step for you because you are moving too fast. On the other hand, if you both have been together for awhile and your relationship has had the opportunity to endure hardships, problems, disagreements, everyday things and occurrences, and you both work well together, then marriage may be the right step for you both.
Another important test is if you both live or have lived together and you know each other’s living habits, routines, quirks, bad habits, behaviors, mood swings, and sleeping patterns. If you could both live harmoniously under the same roof it is a positive sign. Some people cannot live under the same roof together because they are just too different. Say for example you like everything in a certain spot and neat and clean. The only thing that ever gets under your skin is when people are messy. Then you get married and she is a completely messy person and would prefer her place a pigsty. Not to say that this situation couldn't work, but the odds are a little slimmer.
Another good indication is compatibility. If the two of you are completely compatible with each other, there is a good possibility marriage would be the right step. Do you two balance each other out? Is she the yin to your yang? Does she help in making your life feel more fulfilled?
There are other vital questions to knowing whether or not you should marry your girlfriend. Does she make you happy? Is the relationship an even balance of give and take? Do you see your future with her? Can you see a future without her? Does she make you happy? Can you handle her at her absolute worst, and she yours?
Marriage is an important step to make, but it needs to be done with the right person.