Hello Juan, I woke up and thought I would check to see if you're OK.
It is very very very 
early days yet, it is absolutely natural that you should feel conflicted about moving forward without Mark physically by your side. I remember being invited to a BBQ 2 months after DH died and feeling disloyal because I was at a social event without him. Those early months were all about trying to get my head (and heart) around his loss as he died very suddenly (no prior warning). Looking back, I went through all the disbelief you are experiencing. It's all consuming and overwhelming.
There is no discernible time when the pain-like-shards-of-glass through my heart lessened, it just sort of faded over a very long period, but even now some years later, I still mourn his loss and that will continue for all time, because our love was wonderful and life has this bloody awful habit of kicking us in the teeth when we don't expect it.
Please don't you dare feel bad, self- conscious or attention- seeking for your grieving, you have every right to feel whatever you want. There are no rules, remember. Just be the lovely person you are, take it nano-second at a time, and don't expect it to make sense. It won't ever, so don't struggle to rationalise, or regret, or expect anything predictable to be involved in this mourning process. The feelings will ebb and flow, you will think you've cracked it then, Bang! Something will happen that reminds you of Mark and it could set you off. Then you'll realise, I love that man so much, I still care and how wonderful to still feel upset ( it's a comforting thought, in a weird sorta way).
Main thing is, try to do one nice thing a day, anything, and if you find some happiness you can say to Mark that he can be at rest and not have to worry because you are fine. Don't feel bad in other words, feel OK with it. for his sake.
It all takes a lot of practice! xx