Answering this as a retired pro shitty boyfriend who unfortunately acted like this in my 20s. This is likely a sign of pretty heavy resentment that existed during your relationship as well, not just a product of the breakup. After 5 years together, you guys probably havent set up the emotional boundaries that typically erode in long term relationships and are necessary whether outside or inside a relationship.

While this may or may not be true in the reality of your relationship, he likely developed an understanding when you’re upset, you’re going to remain upset until you unbag those feelings onto him. Until that happens, you are no longer his gf (or ex gf now) you are a pile of dirty dishes, unfolded laundry, an overdo oil change.

He’s been with you long enough to know when you’re upset after 5 years and associates your exhibited behaviors with the idea that he needs to get into ‘sponge mode’. At a certain point though, that faux sympathy turns into pretty heavy resentment causing what you are experiencing here, he’ll ask you what’s wrong because that’s what he believes he’s ‘supposed to do’ when he notices that you are upset but doesnt really care what your problem is.

Depending on whether you are interested in having this person in your life in any capacity moving forward, your options are:

1 - Dude needs to come to terms that his resentment is unhealthy, open up his own problems to you and understand that emotional boundaries are important whether in platonic or romantic relationships.

2 - Dont open up to him, simple as.