My story has some similarities and some differences from yours, but long story short my husband also left and I have a 3 year old daughter, so I understand the added difficulty and pain of dealing with this with very young children to care for. I remind myself how strong I am and how proud I am of myself for being a GREAT mother through all of this, and so I’ll remind you of how strong you are too . In some ways I almost think of it as an advantage; my daughter is a constant reminder and reason to be my Best Self no matter what, and I have to think that has helped my situation with my H at least a little bit.