First, really sorry this is happening to you. Terrible.
Secondly I’m not sure how it would look if we get married asap and then apply. It would clearly scream it’s for the visa, technically yes but still how does it work in this case?
It will not hurt your case, it will help your case. Yes, it will still get reviewed carefully given the previous rejection, but the 'technical bar' of common law can actually be a bit difficult to meet.
You and your spouse - having lived together quite a bit and longer together (even if apart) since then - will have a thicker and better documented file if you apply again.
Getting married will help your case.
Firstly I don’t want to get married just to be able to get a visa. I want a beautiful wedding ceremony with family and friends. It’s difficult and expensive (and also not easy due to covid) to perform since all of them are all over the world. It doesn’t seem right to rush something as important as a wedding day. Maybe I’m too naive or it’s just like having different views on life since I’m still kinda young and people of my age are fine with being in CL relationships.
Okay, I'm going to make some comments that may not be welcome, but you're an adult.
Big one: you can get married any way you want. You can have eight weddings if you like.
And you can do what many, many tens of thousands of couples do in almost all of Europe, Russia, and Canada, which is have a modest, small civil ceremony, and then have a private / religious / enormous / scuba-diving / whatever-you-like ceremony as beautiful as you like, whenever you want.
A civil wedding is a civil, legal ceremony. You can combine that with your big beautiful wedding, but you don't have to.
And the point I would say you ARE missing a little is that the point of a common law relationship having some status (historically and the way I think they approach) is that a real common law relatonship is every bit as real and serious as a 'civil marriage.' (Including legally depending on jurisdiction, but really complicated).
Whether it's naive or not, I don't know; but if you see a difference between 'getting married' and 'common law' to the extent that you don't want to get married for a (rather important) immigration reason, then you are actually demonstrating that you don't see marriage and common law as the same. You're kind of undermining your own case. You're not getting married 'just to get a visa' - you're getting married in a civil ceremony a bit earlier and in different cirumstances than your dream wedding for a really good practical reason.
Whatever your feelings about marriage: right now, not being married is one barrier (partial anyway) to you and your spouse being together where you wish to be. It's up to you to decide whether that's worth it to you; but it seems a small price to pay. Practicalities are another difficulty, but this is one thing you can actually do.
(None of this excuses in any way how those who reviewed your file handled it.)
And for others who may read this: yes, we do see cases like this where common law status is not accepted, or the relationship itself questioned. Twelve months living together should be seen as the MINIMUM. And that as well as other signs they'd like to see can be hard to demonstrate. Worried about your immigration file? Live together AND get married.