Comprehension sneaks up on you, and better comprehension takes longer.
So, I was a nurse and suddenly I heard the word oer, cold. I’d learnt it in class (this was before SSIW) but then my patient said it. And it wasn’t about the weather, it was that she was cold and wanted a blanket.
SSIW is primarily Say SIW. It isn’t read, write, or even (sorry Aran and the team) understand SIW. It’s grammar lite. You are given listening exercises, but if that’s all you listen to, that’s all you will (eventually) understand.
In my personal opinion, the more contexts you use your language in, and the more more contexts you hear the language in, the better. You know this, you find it hard. What I could suggest is falling madly in love with someone who will only speak Welsh with you! I can’t motivate you, I can’t make you like things.
If you remember why you want to learn, improve, your Welsh, because, honestly you are better than when you started, that’s a good start.
Who do you want to speak to? What do you want to speak about? What do you like to talk about in English? Go find people who are interested in the same things yn Gymraeg. I know it’s hard, but you can’t learn a language, either to speak it, or to understand it, without real people at the other end of the conversation.
Also, pick your battles. I’m studying theology at the moment, In English. But there are large portions I don’t, on first hearing or reading, understand. There are bits of medical stuff I don’t understand, despite a career in nursing. So don’t expect to understand everything, And thus, don’t beat yourself up about stuff you don’t understand.