Im so sorry he did that to you. Gambling, like any other addiction can only be tackled by the addict themselves. The AA mantra is used for a reason 'You did not cause it, you cannot control it and you cannot cure it' you will never be financially stable and able to provide for your daughter while he is pissing your money away, his need to gamble is always going to take priority over you and your child, whether that be luxuries or the very basics like food and warmth.
He is violent, you do not have to accept that and it is not your fault. In a marriage you row, conflict is part of life and resolving it never, ever, involves using violence, coercion or fear - never.
It will be less painful to minimise what happened, put it down to a loss of control and one off mistake, he will likely pressure you to accept what happened and carry on as normal - this may be by way of huge and emotional apology and promises or by denial, gaslighting and blame. Neither is ok, neither guaranteesit won't happen again or assure your safety. Once that line has been crossed violence often becomes more frequent. Even after all the guilt assuaging tears and sorries.
It is scary, the whole situation - the aggressive conflict, the assault and the fear of the unknown - it's ok to be scared by that. But, to be paralyzed by that fear puts you and your dd at huge risk of harm.
I understand why you may not feel strong enough to leave right now, but reporting this crime to the police is the first step in getting a free and safe future for both of you.
Please call Women's aid and let real life people with solutions help support you. Please call the police.
Are you safe now? Do you need to go to hospital to check your injury?