Working through is realizing that all dear old moms who look alike, aren't, and that person in front of you probably isn't going to hurt you, based on experience now (relying heavily on the logic of knowing that person in front of you doesn't know you, why would they want to spend the energy hurting someone they don't know and how could they, since they don't know you specifically enough to know what would hurt you: you're as different as they are).

Until now, you have been looking at all the dear old moms without knowing it, concentrating on this "mass" of beings and not able to differentiate (think Matrix with them all Agent Smith, Brown, Jones, etc.) but now you know your dear old mom better and can compare/see some slight differences. Not all mothers are turkeys raising their children. You'll be able to pick out some while shopping who aren't, who listen to their kids and try to help them while everyone is shopping together or you'll notice other moms who might be turkeys but they're turkeys in different ways than yours was.

As you get better at identifying the differences, you'll get better at dealing with the individuals, get more self-confident that you can differentiate and deal by yourself. It's a matter of practice; you haven't had any experience so you're new at it and it's of course scary, you're not sure you can do it. Working through is just learning something new, can be made into an intellectual exercise almost (at least you can think of it that way, can't practice it like that though).

Find more easily differentiated individuals who aren't as scary to take on first (I love sales/grocery clerks; you can ask them inane questions like when they get off work, get their next break, ask them aren't they glad they're indoors when it's cold or rainy, etc.).

Make it a bit of a game; see how many people you can start a conversation with in a single day or dare yourself, when one greets you, to tell them something personal about yourself (that you're tired because you didn't sleep well, the neighbor's dogs bark too much, you like rain because it gives you a bit of a rest from your depression; it's harder when you feel depressed when the sun is out, etc.)