It must have been quite the shock for you OP. You were happy in your relationship, your life. Yes, it would have been nice to do theatre trips, weekends away too, but you were content to do without because you expected that in a couple of years he'd have finished his renovations, return to full-time work and with his finances being less on-the-edge he would relax and feel able to do theatre trips, weekends away etc.
But now, that you know his being skint was all a lie, a lie that he repeated and reinforced constantly - it has all gone. This new piece of information about him has given new meaning to everything that has gone before. All his lies - and they've not just been about his claims to be skint - are now sitting exposed. And it's not a pretty picture.
Renovating his house - well, it's a lie, isn't it? That house will never be renovated. His part-time job involves a 2-hour round trip - daily. If his company was willing to let him go part-time, they'd have been willing for it to be over, for example, three full days, giving him two full days to get on with the renovations. Or, as an IT consultant, that's perfect for WFH with maybe the occasional day in the office. His current work arrangements however, are perfect if he wants to minimise the amount of time he has to spend renovating.
And now that you're looking for logic, you've seen other illogical things. You're connecting the dots, now that you realise they're not just dots they're a pattern.
"He has gone part time, losing £28k a year to free up his time. He will then spend that free 4 hours that he isn't earning money scouring one charity shop after another looking for clothes and bent brown frying pans. Then when he gets home he's too tired to do any work."
So he trades income for time to spend renovating - but instead spends it in charity shops? Again minimising the amount of time spent renovating, pushing that end-date back and back and back.
"Surely it would make more financial sense to spend that four hours working on his renovation project then hop onto ebay or amazon for five minutes before bed and spend £10 on a tee shirt?"
Yes, it would make far more sense. It would also make more sense if he'd stayed full-time and had another £28k to spend on tradesmen - but that would speed up the renovation.
"He says he cannot predict how long the house renovation will take because he won't employ any help so everything from gardening to plumbing to plastering to kitchen fitting is all down to him and he is learning as he goes from Youtube videos. Every time he pulls a muscle, sprains an ankle or gets a cold he stops work until he's better."
You thought this 'not employing help' was because he wanted to be able to look at his finished house and to be able to say, with well-earned pride, 'I did that!'. But now, seeing the bigger picture of who he really is, you can see that it's all aimed at slowing the renovations down. The renovation will NEVER be finished.
But it's not meant to ever be finished. It's meant to provide him with a story that people will believe. Renovations are time consuming and a total money-pit. I've done some, I have family members who have done far more and devoted years of their lives to the task. Of course, they intended to finish. Took on second jobs to pay for proper tradesmen, the lot. Relaxed in their beautiful homes at the end of it all. Their renovations were not a cover-story, not a disguise. His are.
I think the person who pointed to Financial Hoarding Disorder might be on to something. He has it, just as his mother is a more conventional hoarder. ANd he is bending his life all out of shape because of it.
More importantly, he is bending YOUR life out of shape. You have willingly done without the trips, the holidays, the restaurants that you can afford and would like to do, because he convinced you that he can't afford it and he convinced you that he was too proud to let you sub him and he convinced you that "yes if things go well we will have lots of holidays and days out and meals out and trips to the future."
How do you feel about him manipulating your life in this way? Because yes he has told you lie after lie; and those lies have manipulated your choices to suit him. That's the man you're in a relationship with. The one who on the surface has "similar hobbies, outlook, politics, music taste, humour etc." and that you found "incredibly sexually and emotionally attractive", but who, hiding behind an endless 'renovation' is more than happy for you to go without the experiences that make you happy. His focus is not on renovating his house or being with you - his focus is on the thrill of buying a tee shirt from a charity shop for 50p.
He's not the man you thought he was. He just looks very, very like him.