Retirement tax questions

Thank you for the detailed answer.  I understand the loss of certain credits when MFS but was looking for information on a dependent care FSA (reimbursement) account.  I have seen information published that the limit is $5000 for married filing jointly and $2500 for married filing separate but cannot find clarification on whether both parents can have an FSA for $2500 or only one.  We both contribute equally to dependent care and expenses