Hi Zeny,
I'm Not against you going out with B if A doesn't respect your
feelings, since I dunno you personally, I can't judge 
However, I would like to caution you against entering another
relationship so soon after 1 relationship ends. Give yourself some
time to get rid of the emotional baggage before you make the choice
whether or Not to get involved with B.
It would be regrettable if you enter into a relationship with B at
the time you're most vulnerable & needy of attention, &
after dumping your emotional baggage, you realise you're Not really
in love with her at all.
If you feel that there's No hope in your current relationship,
& this gf is doing you harm to your self-esteem, then a split
may be the way to go. However, allow yourself time to sort out your
emotions, & date. If B turns out to be someone you fall in love
with, then by all means
FeowFeow
