There are some things that are outright abusive (violence, gaslighting, isolating the victim etc) and some things that are blurry. For example, if you are terrified of spiders, and your partner continually brings spiders in from the garden and puts them under your nose, this would be abusive. If you loved spiders, this might be a really nice thing to do.
The label 'abuse' can be something that can stop a person from responding appropriately to poor treatment, ie the victim could end up saying 'Oh well, it's not abusive to bring a spider into the house, so I shouldn't make a fuss', and putting up with years of feeling on edge in their own home.
You get to decide where your boundaries are. If they get crossed, you tell the person, calmly, that what they did made you feel bad. If they then continue to do it, they are not respecting your boundaries, and you need to take appropriate action to make a distance between them and you.
Have you explained to him how you feel when he makes these comments, and when he ignores you? If so, what was his response?
Keep in mind that PND will isolate you too (or make you feel isolated), so staying with him and allowing him to worsen your depression isn't necessarily the best way to avoid isolation.
Being ignored when you cry, and feeling that your partner doesn't care that you're upset, is enough to trigger depression on its own. You must be really hurting. There is a way through this, and you'll find it 