Maternity pay help

I am receiving 948 in statutory maternity pay and I am struggling financially. For context I live in London with my partner and we split bills evenly. My side of bills total to 1100 every month. My husband doesn’t earn a lot and relies on me in terms of my part of bills, we just about break even every month on my regular pay. My husband is supportive and says he will do his best but I’m really worried. I’ve got paid the statutory pay today and all my bills have gone and it’s left me with nothing. I live with my MIL and BIL and they’re just as useless as anything, my MIL claims benefits but that barely covers anything and she always stresses my husband out demanding more money, she also wastes so many things like food etc What do I do? Can I claim any other benefits? Can I claim universal credit? I also suffer with PPD and this is one of the things and depresses me