My boy friend is addicted to jack’d? Grindr?

We have been together for 4years..we are late 20’s. and so far we have almost borken up 4times as I found he has used gay chatting apps and met some guys... we really do love each other, live together and settled down like marriage couple. Last time when I found out he had one night stand, I decided to give him one last chance and he wanted that too. But he did it again... he said he really love me and don’t want to break up but it is like addiction when he is bit horny he keep using apps and meet up someone.. I think it happens like every 6months or so.. he said he doesn’t know why.. and I don’t know what I should do... We don’t want an open relationship and don’t want to break up but how he can stop being addicted to these apps...?