Can headphones ever be as good as high end stereo?

Different!

Talk to your spouse about your listening habits. Try to reach an compromise about when you can listen and how loud (an SPL meter would help).

I don't know what you system is, but based upon your description of its sound I don't think headphones will make you happy. If you want to give headphones a try, you can get an excellent sounding setup for well under $1k.

Headphones are way easier to try and audition than a home system.

The beautiful wall of sound will be different, more encompassing and less in front of you. Some pricey audiophile phones and/or phone amps may attempt to simulate a soundstage and imaging like a good speaker setup.

You might like it better or worse. Speaker soundstage and imaging are the aspects of sound that will most likely be impacted. All the rest could well be better for much less. It all depends on what you value.

I tend to still prefer my speaker setups when I can listen to them but headphone listening time is on an uptrend for me for practical reasons.

I listen a lot away from the house via Plex Media server, which is a very nice very low cost, high quality option for listening via computer audio and mobile devices.

PLEX mEdia server and web site enables listening via any web browser for free and there are mobile apps for Google Android and Apple mobile devices for only $5 per platform. Its a no brainer to try this alongside ones big buck home system these days and see how it goes.

Yet another reason why the future of audiophiledom as we know it looks to include a lot of change and/or expansion from the old, proven, and often quite expensive tried and true ways.

BEing able to listen at volume you want without disturbing others alone is a great reason to add headphone listening to ones arsenal, and hten just let things play out from there as need be.

The upside of your situation is the recent incease in options of high-end headphones and amps; Stax has more competition. I tried a few at axpona and was really impressed with Audeze LCD-3. The downside is the presentation of headphones is in one's head and does not change as you move your neck. I do not think quality is going to be the issue so much as presentation. That is up to you.