If there is one bit of advice I recommend for mums doing it alone, either through the pregnancy, after baby is born ( or both) is that you get some sort of counselling. It can even be someone close to you that just listens to you and doesnt pass judgement but ideally, see your GP and get referred to somewhere like 'relate' or a free ( or small donation only) counselling service. I tried to talk to my family but they always got angry and upset ( not with me, with FOB but it was directed at me) and in hindsight I wish I had gone to see someone and stuck with it. I went once or twice but felt I could cope. I can cope with my baby, daily life, hard work, etc etc but I just cant cope with the emotional pain of what my FOB did. Its like my brain just wont accept it and kicks in to crying mode now if I even mention his name. Don't suffer in silence hun, talk to someone, get it all off your chest. I have months and months worth of anger to get through with my therapist now, wish I had done it before. Heres a website for 'Relate'.
https://www.relate.org.uk/home/index.html
Also checkout 'netmums' and 'Gingerbread'. Good places to find out about resources.