Help me! Merriage

AS sisters. I want to share with you all my story and get some advice.

Im merried with my husband for 5 months. With no doubts he loves me, I love him and I would anything to make him happy and give all myself to him.
On our nikkah i converted from a cristian to muslim because of him (we even didnt celebrated, we had just 5 guests in our wedding) Not because he wanted so or told me do so, It was my dessision. I just felt that islam is better gor me than a religion I was born with/grow up with no matter of my comunity, friends, family reaction. (If im doing any mistakes dont judge me, I'm still learning).
About 3 weeks later he told me about one girl from his country (we are living in Europe, hes from Asia). He told me he needs to merry her because of his comunity, because of his fault noone respects her there because of people talking things are not true. Shes divorsed, my husband is divorsed too, theyr age is save and im 8years younger than him. He has a tatto with her name aswell.
Ar first when he told me I was speachless, but finaly I understood that that would be right thing to do, to help a girl to get her respect from the people back.
During the time I noticed that hes on his phone more than he should be, he start be angry at me just even for touching his phone. I cryed. I cryed a lot because I didnt knew why, what I did wrong etc.
Thats not all. He start to lie me.(I dont know if you can call it lie if he tells me the truth sooner or later).We start talking about that girl and everytime he says something more. He promised me he will never leave me, that hes not going to merry her, or even text her he loves her (One night I checked his phone and found these kind of messages) Untill one day we had a fight about this because nothing has changed. He told me that he loves her, he wants to merry her not because of comunity, but because of feelings, he texts her how much he loves her, sending kisses, when I asked him to remove a tatto, because as much as I know its haram at first he agree, but during the time he changed his mind.
Not a long time ago he told me he already proposed her. That was even before we met, so I dont know should I be agry at him for hidding these kind of things from me all the time we are together?
I dont want anyone to think bad about my husband. He is not bad. He takes care of me. He loves me. He gives me everything I want. But im not the person who cares about material things.
He still wants to merry her(We are talking about this a lot)even he knows how much does it hurts me. He loves us both. And I dont affraid to call myself selfish because I dont want to share. Love is for two people. All love songs about two persons, all love movies about two, but what to do if I feel that the second merriage is going to ruin me.
I hate myself for being so st**id and weak. In all this time we had few big fights. He hurt my heart 3 times. And its all because of her. Because of the angryness He told me that he dont cares about me and I can do whatever I want, told me go and dont come back (Im going to visit my family in my country) and few awful things that kicked my heart so much I even went out from the home with full eyes of tears in a middle of night (3times) I still can feel the tears on my cheaks, how is hard to breath even hear her name... I cant leave him because I know he is that only one who will always be in my heart, and even a thought about devorcing makes me cry. And I still trust him, he cries with me aswell, hes always next to me when he see something is wrong, because he dont wants to leave me, but at the same time he wants to be with another woman. And all Im affraid is future. Im affraid the girl will not agree the share aswell (she doesnt even knows we are merried, she doesnt knows anything) and then he will have to chose. Im affraid he will not want to have childs with me because he wont want to hurt her. Im affraid he will run away without telling me. Im feeling so insecure, so weak and lost. I just dont know where my place is.
So im asking for your, sisters, opinion, advices what should I do?
Continue the realationships and hope the best with a possibility just to die inside and become sick or
Should I finish everything and hurt myself aswell, lose the faith and be alone till the end of life because I cant imagine anyone else in his place?
Maybe there will be anyone with a similar story.
Thanks for the answers.