You cannot claim your GF if she made over $4300 of income in 2020. You say she went back to work in 2020. If so, she can file her own tax return and use the recovery rebate credit to receive the stimulus with her own tax refund.
If you have a child together then only one of you should claim the child as a dependent. The other parent should not enter anything about the child on their tax return.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
