Why am I afraid to be out at night, and how can I get over it?

I’m a mother of a 2 and a half year old and ever since I became pregnant I’ve been especially afraid of the dark. I have always been cautious when walking/busing through town in the dark, something that I picked up from my mother. (She used to always tell me that when in a parking garage I should check under the car before getting in to make sure that no one was under there waiting to attack me.) But since I became pregnant I’ve become increasingly scared to be by my own or with only my daughter outside at night. It’s been taking a toll more and more recently… my partner, daughter and I are moving to a new house and even just the thought of having to get used to new surroundings is making me have nightmares. I feel like I wouldn’t be able to protect my daughter and myself if I got into a situation that required such an act. Therefore, I only feel safe if my partner, or another close friend is with me. Though, remember, I feel safe in my current home (didn’t always) but now I’m moving to a new home. I’m mostly concerned because this same problem happens all the time if I’m outside a night no matter where I live (I live in a very safe part of town). My partner says I need therapy and I don’t necessarily disagree but he gets angry at the same time which makes me feel like shit. I’m wondering if anyone out there has had a similar experience or has any advice. Greatly appreciated either way. Thank you.