Is it permissible to have an abortion?

I have 3 kids(6.3.1). Found out I am 4 weeks pregnant. I live in another country without any family. Husband works 24/7. He is on call all the time, his job is very demanding and doesn't get paid well. We have recently handed in our passports for renewal of our visas and have been told it will be 8+ months before we get an answer and so we cannot travel . We also had to give up our car because we are not allowed to drive until we know our status in the country . So everyday tasks like buying bread and milk, school , doctors have become a nightmare and costly . I am at home with kids and have no access to the outside world . I am isolated . I do all the work with regards to child rearing and running the home . It is extremely demanding physically and mentally. I have no time to take care of myself , pray , eat. I am beginning to resent this life and my husband and the kids . All I do is yell at them and recently have been wanting to physically hit them . When looking for support at the doctors they simply want to prescribe medication to help me cope but I am not keen on it . I have family history on. Other sides of mental health issues and have been working hard to not end up like that . I have asked family for help but the cost of travelling to us and the cost of us having others around is too great . Parents are too old to help . My last child was born early because I was extremely ill during the pregnancy and was very physically active due to all the responsibilities I had to take on. Another factor is if we had to have this child and add them on to our visa we would have to pay +- 25 000 Zar. I simply cannot cope with another child . While typing this I am having an anxiety attack and wish to run away and leave the kids . With my previous 2 pregnancies my husband also was on drugs and became physically and mentally abusove . Is it permissible to have an abortion?