Honest but respectful opinions. Would you eventually leave?

I’m gonna post anonymous because I feel this is a touchy topic. So my husband and I been together for almost 5 years and having our second baby very soon. For the most part my husband is so loving, caring, sacrificing man you’ll meet but once he doesn’t like something or doesn’t like if someone did something he will go on long rants, majority of the time it’s me he rants to, he won’t really show it to others, but his rants consist of being mean, or just aggressive. I know he does have some sort of anxiety and depression but he doesn’t do much about it, i tried going to therapy with him but never happened. My sister is getting married in two weeks an he’s been a wonderful help with the planning but once he’s in a bad mood he’ll say things like I’m done helping, I’m so sacrificing, I’m too nice. He won’t show this to anyone but me and I’m his wife so I understand he’s venting but sometimes it puts me down. We have had bad fights nothing physical in the past he’s made a scene in front of my family couple times but it’s been years an he’s gotten more mature so he’s better. Idk I’m just overwhelmed, I’ve had plenty of talks with him an he understands where I’m coming from. He even left me a “thankful for you card” this morning. He said hes the luckiest guy to be with me. My husband is overly sensitive and emotional so his moods can be hard to deal with. I go to therapy an she gives me good advice but I let my emotions take over too. Hes supposed to take my sister and I a couple hours away from where we live next weekend so she can get her wedding dress but I’m afraid he may act weird an not want to. He’ll think about himself at times when he doesn’t need to. He didn’t go to my best friends wedding because he said he’s done being so nice and wants to focus on himself, I don’t think that was the reason, I think he was in one of those funks. Any advice or opinions that are nice will much appreciated