I have a lot of sympathy for what you are going through here. You love this girl but she does not seem interested. Please don’t feel hurt as life is sometimes unfair. The message she seems to be sending you is quite negative as she is even ready to marry someone else. Please give it another try and if you can see there is nothing positive coming your way from her, you should count your blessings. Remember, you must be lucky. She could have fooled you and once you invested so much energy, feelings and time she could have run away with someone else. That time could now yours to invest it in positive thinking, happiness and meeting other people.
Good luck and wishing you all happiness in the world.
Very best wishes