My boyfriend keeps leaving and coming back.

My ex and I have broken up three times, he has been the one to initiate the break up every time without warning and for no reason other than "I need to have space." He has also been the one to say that he missed me every single time. I want him back more than I can say but I feel like if I let him back he will just keep breaking my heart. He just told me two days ago that he wants to come back to me. How can I stay with him and make our relationship solid?

He doesn't breakup with me and hook up with other people By the way. Even his mom and best friends told me he has been completely single.
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+1 y
I told him not to call me or even consider trying to get me back until he can tell me why this time will be different...idk what else to do.
My boyfriend keeps leaving and coming back.
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