Alright, so the discernment portion has been on the table for awhile then. I would guess then the only real “objection” people may have is the timeframe between ending the relationship and the present day.
If you’re not comfortable with your diocese’s formation and vocation programs, that’s fine. Speak to a couple of other vocation directors and pick their brains. I mean, if they say “drop by and stay for awhile”, excellent! If they say “not right now”, ask them for concrete steps on how you can prepare yourself for this vocation - especially if they say “you could use more time after your previous relationship, so wait a bit”. I would also circle back and ask the rector of the SSPX seminary for his advice on what concrete actions you can take - do not settle for “you were in an unchaste relationship” as being the only answer to your inquiries, unless he provides additional context like the years removed thing.
Lean on your spiritual director during this time. Ask him for prayers of course, but especially guidance. I certainly do with mine, and as someone starting as a spiritual director, I find that when it comes to vocation stuff I want to provide concrete suggestions - even if it’s logistical ones.