Guy's Behavior

Shall I go back to my ex who loved someone more than he loved me?

Everything was fine but we broke up because our families won't agree to us.. it was scary asking them about it!! Then he moved on to a new city & he developed feelings for some other girl & he was into her more than he was into me though we dated for like 5 years (it hurts to know this)..
They both liked each other but didn't date for whatever reason.. Loving her made him realise what I must have gone through the relationship where one person loves the other one more, like the small efforts when it isn't there it kills you from inside, he has gone through all of it & he realised my worth.. He still talks to the girl everyday, he made it clear he wants nothing but friendship with her! But I don't believe him!
He asked me out & said he is sure about me & will do everything to make it work! I don't trust him with that because if being with me for years he didn't had the same feelings how can I expect him to develop it now? Nobody can force their feelings! I was single all the while, ofcourse I love him but I can't go through the same pain again! I don't know what to do?
Shall I go back to my ex who loved someone more than he loved me?
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