Found out that my husband been cheating on me for years.

TL;DR: I found out my husband been cheating on me for years. We loved each other for more than 12 years, we are married for 4 years. Now I found out he got a lot of other lovers from a long time. He changed alot with me he isnt willing to stop and I dont want to break our relationship.
Hi, I am new here and I decided to join seeking an advice. I am very broken and depressed that I started to forget the date and day.
I am married (28F) and I have two babies. My husband (30M) and we knew each other since I was 16 years old. We loved each other, or I only loved him I am not sure but we were happy we maintained our relationship and we got married and everything was fine until the last year.
He started changing everything changed almost even the way he talks to me. The way he treats our kids, the way he argues with me, our sexual life, literally everything. I found out he got alot of ladies on his phone, alot of porn and lots of love chats with so many females.
Few days ago he was too busy on his phone and I decided to sit next to him to have little chat. He got angry and said "why would you stick to me do you believe I love you that much? "
He lost his job in 2020 and when I asked him why he is doing all this he said he is stressed. But then I found out he has been cheating on me for years. Alot of old contacts and alot of old chats all over his phone. Its just that its becoming more now. We argued and he promised not to do that again. Its been few months and he never stopped. Its so hurtful. Its really hurting that he is being dismissive.
I argue with him everytime about how hurtful this is to me and how much sad I get he simply apologizes but never stops it.
I used to have his phone password now he changed it and he is on it most of the time.
We faught about it several times and he never cared it even reached hiting and he was so aggressive, eventhough he was never like that. And I forgave him as well. He never cared to stop he just says sorry everytime and hides his phone again and again.
I just feel stupid and weak. I am so weak.
I really dont knw what type of actions I can take, what can I do to bring back the life I had with him before. Whenever I remember he have been always like that and I just found out about it, I break more. I just dont want to break our long relationship. I might lose myself.
I forgive him everytime, we talk and live normally until it comes to this argument he isnt willing to help. He spends more time on his phone. I work, I pay for all expenses he thanks me for that. He promises to compensate me when he finds a job and then he goes back to his own world.
I really dont know what to do. Why would he cheat on me? Was I never enough for him? Is there any guy here who knows how would he be thinking?
He never complained I always ask him if there something he doesnt like in me and he says no I just love you. He has been lying all these years?
I feel I am too blind I just cant understand whats happening. If he doesnt love me why did he stay with me all that time and then married me?
What really broke me more is when I asked him this question he said " you loved me and were good ". So he is saying all the time he was with me because I loved him and I was too good? So he never loved me or what?
And now he says he was just too angry he does love me. What should I believe :(?
Talking to him about it is useless.. he even stopped answering me when I argue about this. He never explains.
Why is he assuming I should just continue being hurt and live normally with him?
I cant tolerate the pain I have in my heart I am forcing myself to work, take care of the babies and yet think of all this


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