My boyfriend has a second boyfriend

Me and my boyfriend opened our relationship in April of this year. He got very consumed with meeting new people and eventually found a guy he‘s dating since the last two months. He only sees this guy now and he meets him 2-3 times a week, for evening or overnight stays. He says he is in love with this guy and currently only wants sex with this guy. He says at the moment he appreciates life more with that person. But he also confirmed that he still loves me, however "in another way".We‘ve been together for 10 years (both are 30 now). We live together, both work in management and we have a prosperous life together with almost no problems, except this new development. The other guy is in debt, and has not even started his university education. There are many reasons why it would appear absurd for him to leave me and commit to this new person. However he says the craving is just there and he does not know how to stop it. I want him to be happy but think he‘s deluded. I would wish that our life together could just continue as it was.I am aware of how the human psyche works. Humans get dissatisfied after a while, independent of how good their life is. The ego is never happy and continuously looks for fulfilment in the future. Even if it reaches what it thinks it needs, it quickly gets bored again. I thought I will let this unfold and hope he will see that also this new guy will not provide the happiness he seeks (this he can only find within himself). However I‘m not sure wether I should request a decision from him: Either me and we try to re-fuel our love OR him.How would you deal with this situation and what would be your reason? Any help is greatly appreciated.