Based on your story, he looks like he's cheating on you. He wouldn't want you to visit his new place cause his bathroom is dirty? DUH. I don't believe that he's always having overtime at work. what type of work is he doing? If I were you, I'd surprise him at his workplace or during lunch break or at his place to see if he's really hiding anything from you. You have to investigate for your peace of mind.
Agree. Turn up unannounced. IMO, may parallel life na yan establish na he is kuno single, etc etc. Pwes, make it hard for him to maintain his story-telling-a-lie-life. Insert yourslf into his life, circles, friendships. Shake it up a little -- naging pabaya ka din, really. Do not be complacent, remain a challenge for your man always -- IMO, kelangan may konting takot a man sa wife/partner nya or else -- He will take her for granted & likely to give in to temptation.
Given matagal na kayo -- it is but normal to expect you 2 make serious plans, whether married or
otherwise. Like, buy a house/condo, travel abroad, etc. Even a kid. Normal progression of a long-term
serious relationship mga yan.

If he is working OT - the extra funds should benefit you too, 7 years na kayo eh. If lalo ka spending to
keep this relationship going -- - IMO, bad news (as your mom said nga) -- & as I say: Numbers/pesos don't lie.
Hwag ka na mag antay to get irrefutable/solid evidence. First it's hard, in at least 2 aspects. Hahaha
Example: mahuli mo magkapatong. Classic example eto ng lolo ko. The husband will never admit. He will say: Hindi ako yan, nananaginip ka lang.
If you don't get into a crime of passion right then & there at umuwi ka, at mag usap kayo -- per my lolo, ma sweet talk si wife to think: 1 night stand lang yon, lasing lang si hubby, etc etc etc. Coz per my lolo, wives don't want to face the truth most of the time -- too hurtful, and they are scared the husband will not choose them & the kids.
So, for me -- talk to him & tell him if you will drop him like a hot camote or you wanna revitalize your relationship IF he is betrayng you now. BUT whatever his reaction -- if you really wanna get near The Truth -- pwes, PRESS your presence into every aspect of his life. That way, he cannot run 2 parallel lives. If he wants to go on with you -- konting adjustment yan. Pero if happier sya sa other life nya -- magkakabw1sitan kayo. Good, at least you read the writing on the wall. Remember, Love can not be forced -- kahit you have a history of 50 years. Better you know sooner than later, if you are gonna part ways.