A boyfriend, girlfriend, or significant other can be claimed as a dependent if they pass some of the same tests used to determine if your child or relative can be claimed as a dependent.
Since your fiancee has unemployment income (which is taxable for federal purposes), you should calculate your taxes both ways (both claiming her and not claiming her as a dependent) to see which is most beneficial for you both.
Here is some further information on requirements that must be met to claim your significant other:
First, your significant other cannot be claimed as a dependent if they are eligible to be claimed as a dependent on another tax return. Whether your boyfriend or girlfriend is being claimed is irrelevant, it’s the eligibility that matters. Once you see the rules, especially the residency and support rules, this will make perfect sense. So, if your significant other’s parents could claim him or her, you cannot. Your significant other also must be a U.S. citizen, resident alien, national, or a resident of Canada or Mexico.
That’s the first phase of tests.
If he or she passes those rules, these four “tests” will need to be passed to qualify as a dependent. He or she: