Rouky - I will confess that I'm not up to date on your sitch but just thought I'd drop off a few thoughts.
You are still very focused on your H and OW and their relationship. As I said I haven't read back to see if your H is currently engaging in other MLC madness or not so what I say might not be relevant. It would appear that you want your H back and are very jealous of OW and confused as to all of the "why" of this. I will admit to similar confusion in my own sitch. Some of the advise I've been given that I try hard to follow (and regularly fail at) is to let the MLCer take their own journey while you take yours. Someone else posted a comment for me if I remember correctly - "don't try to understand crazy".
For yourself, you seem to be wanting to enter into a new R yourself. Are you sure you're strong enough for that yet? I'm positive that you have a lot to offer because nobody who is here doesn't have a bunch of good qualities. As long as you're still attached to H, honestly are you ready for your own new journey?
Being a guy (I just checked ) and having practically no knowledge of dating sites you may want to do a "180" on that and think hard about what sort of guy you want to find and where they can be found. Are you looking for a guy who volunteers for good causes? Many mature single men do that. Are you looking for someone who loves sports and an active life? Life passes you buy if you sit still and trolling the internet for love, while it may work isn't the only way. My own daughter though met her H on the internet but it was through a chat group about a topic of mutual interest. They've just had their 4th wedding anniversary and are very much in love.
On BD H52, W50 T27, M26 S21, D23 BD-9-Mar-16 D-15-Jan-18 Final-19-Apr-18 I am a storyteller. The story may do you no good. But a story is never for the listener. It is always for the one who tells