No judgement from me – we’ve all been in situations where we knowingly have done the wrong thing and this is often a reflection of the circumstances in which we find ourself.
You have acknowledged that effectively dating a man who is committed to another woman is not appropriate so I am not going to lecture you on why that has to stop… you know that already!
Of course a break up after a lengthy relationship is going to make you feel an element of loneliness. The comfort blanket of knowing that there is always going to be somebody at home has been whipped away from you and you are inevitable having to adjust to living without it. This is awful, and I am sending you the warmest virtual hug.
You went out with your friend and met somebody that you clicked with very easily – what is to say that this will not happen again? Do not waste your time on a man who is playing games when you could be out meeting men who like you and find you as attractive as this guy did, but know what is an appropriate way to act. I fear that by going back to this guy time and time again for dates and conversations, you are again wasting time that could be spent with a good person.
That said, my advise would be to completely detach yourself from any sort of comfort blanket all together, for the time being. You have been in a relationship for a long time, from a very young age, so you don’t know who you are as a free standing, responsibility-free adult. Be single for a while and get to know yourself, what you enjoy, what is important to you and where you foresee your life going in the future. Do not look at a second lock down as a never ending source of loneliness, look at it as an ample opportunity to take time out from the world and get to know yourself. Going out on dates can be a fun and informative way of figuring out who you are romantically but my advice to you would be to not seek commitment at this stage. You have been in a relationship all your adult life, so commitment is what comes naturally to you, however, push yourself outside your comfort zone and meet people without the expectation and hope that is must go somewhere.
Surround yourself with friends and people you love, even if it is virtually, this will undoubtedly help with the loneliness.