How would I know

How do I know if he’s the right one to marry, he accept my children from my previous relationship & he makes me so happy ,he’s there for me but Idk if this will all change one day or if it’s real we been together 9 months now he said by next year he would love to make me his wife I’m scared of falling & giving my all to just be disappointed all over again what can I do ladies ? Don’t bash me I don’t want to hurt again