I can relate. I've sewn since Home Ec in the 8th grade a few decades ago but am fairly new to quilting. I started with easy jelly roll type quilts and then took a step forward to cutting squares and then a (tiny) bit more complicated piecing. I have learned something with every single quilt that I have made. Every single one of them. Mostly what NOT to do! I look at some of the quilts on here and don't ever see myself being quite that intricate with quilting. I always have messed up blocks or test blocks which I use on the back to make it more interesting and make sure I don't waste the fabric. Quilting is not the same as sewing clothes or other items and I did not expect it to be that much more difficult, but...I have found that I don't know as much about sewing as I thought I did! I've not had one quilt happen as planned. Yet. But I keep trying and know that the learning curve will be frustrating for a while. Keep going and move on the the next one -- every quilt gets easier in some ways and you get more experience. Just be relaxed and flexible about quilting, & adapt and overcome when you get frustrated.
So don't feel bad. Your mom is right about the "charm of handmade pieces." Every one of my quilts so far has had some really bad mistakes but I've still donated them to charitable needs and they've always been appreciated. So I'm going to do three things: keep enjoying the process, try to somehow compensate for mistakes so the finished quilt doesn't look too bad and definitely NOT aim for perfection. I focus on the recipient of the quilt I am making and that makes the (mostly) fixable problems I run into seem not so bad after all.