How do I love other people?

My mother passed away not too long ago, and we were super close. Now it feels like there is a gaping hole in my heart where she was. She was my only parent, we have a small family, I have no siblings, we moved a lot, and I was even homeschooled part of my life. My entire life has just been the two of us. We had a lot in common and were best friends. She said she loved me more than any other person in the entire world, and I felt the same about her. I didn't want to get married or have kids one day. I just wanted to live with her for the rest of my life, and she was more than happy with the idea of me never moving out. We were like soulmates on a spiritual level. Loving only one person intensely is the only way I really know how to love. I can't comprehend within myself how people are able to greatly love multiple people- siblings, two parents, in-laws, etc. But in order to move forward and find love again- I know I will likely have to learn to love this way. But I honestly don't know how. I try to imagine/fantasize myself one day with a child, a daughter/son-in-law, and having grandkids to dote on. It might sound silly?? but I can't picture it and there is a lot of internal conflict and even heartbreak when I think about it. And it's also hard to know that I will likely never have someone again that loves me with such intensity as my mom, and only me. I'm at a loss and don't know how to move forward in life. Loving one person intensely- and being loved back with that same intensity- is the only way I know how to love.