Thanks for your question.
Generally, you should receive a reply within 6-8 weeks after mailing your penalty abatement request. If there is a delay, the IRS and/or state tax agency should notify you of the delay within that time and will let you know when to expect a final response.
The only thing about becoming married is that if you later file a married filing joint return and have a refund, the IRS may offset the refund to any past due tax debts you may owe. So if your penalty abatement is denied, they may offset later refunds. The other spouse may file an injured spouse claim to get their portion of the joint refund back though.
Hope this helps,