I need advice please..

My fiancé and I have been together almost 3 years. We have a little boy together and we have been through a lot together. He got kicked out at 16 for skipping with me and we had our son at 18. Lately we have been fighting constantly, I don’t want that for our son but I love him so much. He says I always have attitude which may be true because I’m mentally and physically exhausted between work, having a toddler and then our relationship problems.. My anxiety is at an all time high. Any tips on making this relationship work?