You both need to enter it on your own returns, and allocate 50% to each. You will need to look up your correct SLCSP - the one on the 1095-A is almost certainly incorrect for your situation.
https://www.healthcare.gov/tax-tool/#/
I don't know your situation, but you said you are filing Head of Household ... just verify that you qualify for that, such as living apart from your spouse for the last six months of the year.
In most cases, filing as Married Filing Separately disqualifies the Premium Tax Credit for Marketplace insurance, so your spouse may need to repay some or all of her 50% of the 1095-A.
