Not good enough :(

Mom of 2.5 yo and 11 week old. Feeling so down and not good enough. Always getting frustrated with my toddler and feel like I’m not being present or good enough for either child. My partner is working from home and relishes in the fact I’m struggling. He says I’m wasting my maternity leave. He says he would rather be in the office than have to listen to me shouting all day, our poor toddler being shouted at and how it’s unfair and how I just let her do what she wants (well I can’t be there 24/7 when I’m holding baby all day). Feeling rubbish.