So you are questioning the advice of a professional... someone who (hopefully) has actual qualifications and (likely) a wealth of experience. I don't get it! I'm afraid you sound like you have an unhealthy obsession with exercise. Why do you even need to do that much?! Again, I don't get it.
Have a read up on the female athlete triad. You won't consider yourself an athlete, but I bet you'll find some of the traits uncomfortable to read.
For context - I'm a competitive racing cyclist. I train hard. I also work full time and have a young child. Sometimes, life is so stressful or work so busy/ stressful that it impacts my ability to train and recover.
When I say I train hard. Nope I don't go full pelt. I only do that in the run up to my race season, it's in a managed way and as part of intervals. The rest of the time it's largely very steady endurance paced. It picks up in my build phase, to more zone 3 and 4. But the super steady endurance pace (zone 2) remains constant. There are reasons for this which I shan't bore you with.
If you do any kind of reading up or research on training. It's all about balance between training and resting. Resting means feet up. Maybe a gentle walk. You'll notice information advising you that your body doesn't differentiate between exercise induced stress and other stress. I can't emphasise enough how important that fact is!!
As a PP says overtraining is vile. It creeps up on you. By the time you realise you have it - it's too late. The damage is done. Why risk that? I've been there. In my case it was from the combination of my lifestyle factors AND the training. It'd be the same for any recreational/ leisure/ amateur exerciser.
Now I have a much healthier approach. What changed?! My mindset and confidence in the process and having a plan. I bloody adore my rest days (1 or 2 a week). I bloody love my recovery weeks (I take 1 for every 2 or 3 weeks). It's also about letting my mind recover. I bloody love my off season where I take about a month off any structured exercise regime. I always come back stronger.
There's no reason why you can't have a plan and a goal or goals. A competitive swim perhaps. It doesn't even have to be a competition. I think it's a really healthy thing to do. You can monitor progress and see yourself getting fitter, stronger, faster, better in tangible quantifiable ways. It's very rewarding! With that insane regime you have, I bet your fitness has stagnated. I can't for a second imagine how you are getting any gains.
Time for a rethink eh.