Please help us bring my husband home

I am currently a single mother of 3 children (soon to be 4) aged 10, 6, 2. My life has not been easy having to deal with an abusive relationship that affected myself as well as my first born son and another relationship that resulted in my daughter being molested at 9 months old. My first pregnancy was the hardest. When i was 23 weeks gestation and pregnant with twins, i went into premature labor because of a domestic violence incident which resulted in my first born son being still born and my second born son fighting to survive. I'm thankful everyday that i still have him with me. He (my 10 year old) struggles with moderate to severe hearing loss which is an everyday challenge for him but he shows strength that to this day amazes me. My daughter was born 3 years later after believing i was ready to begin another relationship but tragically that ended in my daughter also being abused at 9 months old by the one person who was meant to protect her. I was struggling with depression around the same time when my only support, my father, passed away from pancreatic cancer. It was so severe that at 163cm tall i was only weighing 42kg. I isolated myself completely to the point of not having contact with absolutely anyone except government agencies that were coming to check-in once in a while. I hoping that one day everything would change and that's when my now husband and i found each other on facebook.
I had met my husband back in 1996 when i went overseas back to my place of birth. Because of the circumstances, i was not "allowed" to keep in contact with him because i was only 14 at the time and if you are at all familiar with Chilean parent's, you are aware that it was a big no no.
Fast forward to 2012, my husband found me at my worst after losing my son, my father, and the troubles i had already experienced with previous relationships and i began to see the light again. He began a relationship with my children via webcam and helped me get out of the hole i had buried myself in after all the heartache. We began a long distance relationship for almost 1 year until we decided to get married. I traveled overseas in May 2013 and we were married June 2013. It was one of the happiest days of my life. I had to return in August 2013 as i was only able to go for 3 months because i was unable to get passports for my kids due to the Father's having to give their consent. My children's biological father's have not been involved in my children's lives at all since my son (10) was 5 months old, and my daughter (6) was 9 month's old.
On my return, shortly 3 months later, i had experienced a major seizure which ended with me at emergency at the hospital. Because of the recurrent seizures and the affect it was having on my children, i was reported to CYPS (child youth protective services) and was classified as an unfit parent because of my medical condition and mostly because i did not have supports here in Australia. My husband an i were going through the process of gathering the paperwork to apply for a partner visa offshore but after so many seizures and constantly being reported to CYPS, i was at risk of losing my children because it was getting to the point that i would be unconscious for long periods of time.
I contacted the department of immigration and we were advised to apply for a tourist visa. So we did, it was granted and my husband arrived in Australia February 2014. He became my children's father and the only father that they have ever known. He showed them support that they clearly never experienced by another person other than me. My kids were actually happy and not afraid to be alone with me anymore. Having your son tell you that he is scared of his own mother is heartbreaking. And that was my reality.
I became pregnant with our son (now 2yrs old) and he was born February 2015. The pregnancy was very hard because of many seizures occurring as well as having to be admitted into hospital to get iron infusions because of iron deficiency i have also struggled with as long as I can remember. The headaches are terrible and constant even now.
At the beginning of this year i became pregnant again and unfortunately miscarried or baby in february. I had to go through the procedure of getting our baby surgically removed which was painful and heartbreaking. I was emotionally devastated. We continued to gather the money to apply for the partner visa and so far we have saved $3500 but we are still short $3500 to reach the goal of $7000.
We continued to move forward and enjoy everyday as a family and then i became pregnant again. i am currently 21 weeks pregnant and am due in December 2017. I am greatful that my husband was here to hear our baby's heartbeat and together find out the sex. It's a girl!
Our happiness turned into heartache once again. Because of the conditions of the visa he was granted after being here in Australia for almost 3 years, the pressures we were facing took their tole on us as a family and my husband departed Australia on Friday 4th august 2017.
I am asking for your help for me and my children to feel completely safe again by bringing my husband home to be with us as a family like it was to begin with.
I am currently registered as a high risk pregnancy and i am scared that my children will be removed from my care now that my husband is not here and that there is a strong possibility that my husband will not be here for our daughters birth. I know that during pregnancy, we tend to be more emotional, but i feel completely torn to the point of constantly crying. I feel like i have lost a part of my heart. I believed that i had finally given my children security until we were faced with this situation.
I am asking more than anything for help to bring my husband home where he belongs with me and our children. I thank you for taking the time to read this. I have already exhausted the avenues to seek assistance and there is no organizations that can assist for this particular reason. I am getting turned away every time. I am hoping with all my heart that he will be able to be here for our daughters birth. I have no one to watch my children while i am going through labor and i need my husband.

Please help.