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I'm hoping to get advice based on real life examples. I'm 38f and have been dating someone (37m) for 6 months. Initially, the relationship was calm and grounded. We enjoyed each other's company and convos and the connection was strong intellectually, and ok emotionally. He's been emotionally expressive since early stages but that escalated to "I'm in love with you" "you have given my life a different meaning" "I've never felt this strongly about anyone, it's a connection of the souls" "I will lose the will to live if you leave me" after 3-4 months.

The thing is, I don't trust intensity. My gut says that intense feelings reside and die soon. And eversince he has switched up the emotional language so much, my trust in his feelings and words have gone down.

I was wondering if anyone here can share stories of their intense feelings (one sided or two sided) leading to a stable long term relationship or marriage? How quickly did you know that you have found the one when dating your now-wife or long term partner?