You are in an abusive relationship and abusers don't change. You can see for a fact that your partner's behaviour is worse, not better.
It's very common for abusers to threaten suicide as it's a way of keeping you under control. You left and went to your dad's and he's still alive so fact two is that he's not going to do it if you leave again. He won't. If he threatens then call 999.
You are not safe with this man. He is violent and abusive and he is not going to change. It also seems as though he's not allowing you to leave the property without his permission. Do you see how wrong that is?
This man is very dangerous and you and your baby are not safe with him. Your baby is not safe with this man and you need to do everthing you can to get her away from him as he could harm your baby. I know you don't think he's capable of that but I'm sure, when you first met him, that you didn't think he was capable of hurting you.
You need to contact your dad and ask him to come and get you. You need to do this as soon as it's safely possible. Please don't tell your partner that you have a plan to leave.
If you can, please get everything together in a bag and hide it while you wait for your dad. Things to include:
Some form of identification
Birth certificates for you and your children.
Passports (including passports for all your children), visas and work permits.
Money, bankbooks, cheque book and credit and debit cards.
Keys for house, car, and place of work. (You could get an extra set of keys cut, and put them in your emergency bag.)
Cards for payment of Child Benefit and any other welfare benefits you are entitled to.
Driving licence (if you have one) and car registration documents, if applicable.
Prescribed medication.
Copies of documents relating to your housing tenure (for example, mortgage details or lease and rental agreements).
Insurance documents, including national insurance number.
Address book.
Family photographs, your diary, jewellery, small items of sentimental value.
Clothing and toiletries for you and your children.
Your children’s favourite small toys.
You should also take any documentation relating to the abuse – e.g. police reports, court orders such as injunctions and restraining orders, and copies of medical records if you have them.
If you can't get these things together, just do what you can and hide it from your partner.
I don't want to bombard you with information and advice as I understand how confused and frightened you are. Please make that call and get away from him.
Once you're away, post back on MN for advice and support.
You're strong and capable and you have to protect your baby so please get away.