When applying for medical insurance will my income be taken into account?

I'm not familiar at all on this. Are you planning to include her in your work insurance? Is that even possible? Or do you mean Medicare or Medicaid? If Medicaid, then they will only take her income and assets. They will do a look back of about 5 years on all her financial transactions. What income she got, and how she spent it. If she gave money to family as christmas or birthday gifts, that's counted as gifting and penalized for it. If she sold her home before moving in with you (within the 5 year look back), they will want to know what she did with that money. Any 'gifting' done - she will be penalized. Very tedious process, sometimes with several times of rejections.