Clearly, there are halachic, spiritual and psychological issues with pornography. Here we are looking at ‘addiction’ to porn, which means that the person feels a degree of compulsion.
An addiction will interfere with your normal functioning, and it will undermine the level of focus and motivation that you could otherwise direct towards dating. Dating takes a lot of effort, which requires us to be highly motivated.
If one’s sexual energies are directed towards pornography, this greatly diminishes a key part of what drives us to put our efforts into dating.
In addition, the addiction scrambles the brain. It becomes more difficult to establish clarity around the place of appearance in the choice of marriage partner.
A further problem is that the person with a porn addiction is often frightened about getting into a marriage, given the heightened risks involved.
Indulging this addiction and dating are incompatible. Get help to overcome this problem before engaging in shidduchim.
Needless to say, this addiction is almost certainly going to severely undermine your marriage. So getting into a marriage before having this issue addressed makes no sense at all.