So sorry you are going through this OP
I didn’t realise that I had PND with my eldest until my second came along. I’d had a really emotional time during my pregnancy with DC1, my relationship at the time with DP was rocky and I was just in survival mode. When DC1 was finally born, the big rush of overwhelming love that everyone bangs on about didn’t come and I just felt numb. Over time things evened out and settled and life carried on and 4 years later I was pregnant with DC2.
Pregnancy with DC2 was opposite to the time I had with DC1. Things were going well, we were settled having moved to a lovely new house, DP had a promotion, DC1 had started school and doing well. When DC2 was born, I had a great labour and water birth that was amazing and this time I DID feel that huge rush of love.
Once back at home with baby DC2 and feeling in the lovely newborn bubble I suddenly felt like their was a gulf between DC1 and I. It’s like I suddenly realised what I had been missing and it made me feel terribly and so guilty. As a child I always felt my younger sibling was favoured and it hurt, there was no way I wanted to do that to my own children.
It was hard at first, but I put lots of extra effort in to DC1, lots of cuddles for no reason at all, gave lots of little jobs that meant I could praise her when she did well (she was 5 at the time.) so she fetched baby wipes, helped carry things around the house for me, watch her little sister for me while I went to the loo. All really small things but those things were helpful to me, made it easy to praise her, ensured she felt involved and grown up and not pushed out by her younger sibling. Every time she did something well or helpful I gave her a little hug, kiss or squeeze and thanked her for helping mummy. I was surprised at how much my feelings for her had changed and seeing how she flourished with all the extra praise and affection she was getting. I’ll be totally honest and say that at first it was really hard, felt awkward and I had to make myself do it. Over time though it just got easier and soon became second nature.
DC1 is 15 now and we have a great relationship and I’m so glad I made the effort back then because it was so very much worth it for what we have now.
I felt like a horrible person and a horrible mother, but I was neither of those things and neither are you. Sometimes the circumstances under which we are pregnant and have a child vary massively between children and sometimes this means it affects how we feel and how we parent. You love both your DC, so much so that you are worrying and posting about your relationship with DC1. You care enough about it to post about it, so say to me the care and love for her, it’s just hard. It won’t always be easy but your DD2 is only young, you’ve got plenty of time to change things for the better. 