Custody after joint living for unmarried dad

State of IL. Unmarried dad with 2 kids where family lived together for 6.5 years (since before birth of 1st child). VAP signed at birth for both children. Last year mom moved out, moved twice, and within 2 months of split moved in with former boss, now her boyfriend. Kids have been split about 55/45 with dad having the kids 55% of the time, mom and boyfriend have them 45% with almost no weekends. Boyfriend appears to be for free rent. I have filed for residential joint custody, but mom is now fighting all time with me, as she says she has all custody rights until a court decides. Mom has began new interest in time spent with children since she knew of impending court actions. Mom is a financial wreck (judgements from IRS and more). Due to papers left behind it appears she had an abortion in 1996, without any info shared with me. Mom refuses to tell me boyfriend address to judge homelife for kids, and states that until the court rules, I have no parental rights.

Where do I stand? Can I object to her living arrangements with the kids and boyfriend?
Thanks

[tbyte]

I don't know what State you live in, but most State have severe restrictions on honoring common-law marriages. You probably do not qualify.
Without that, your State probably has a law stating that the an unmarried mother has full and sole custody of her children by default. You would have to petition the court for paternal rights (custody, visitation, shared-parenting). File for a temporary order immediately.
Without a court order, she is correct. You have no legal rights.
You are going to need a cr@pload of documentation to prove the extent of your involvement in the children's lives. Start hoarding receipts, phone records, calendars, medical documents, etc, like a pack-rat.
File a motion with the court IMMEDIATELY for paternal rights.
Request 50/50 shared custody and settle for no less (you won't get more). You will likely need to pay child support even under a 50/50 plan, so best to reconcile yourself to that indignity right now.

[Postman]

lived together for 6.5 years (since before birth of 1st child).

So, you 2 held yourselves out to the public. HOLD YOUR HORSES 2bit lemme finish.

So the public witnessed your lives for 6.5 years. What about Birth Certs. Leases, voter reg., car insurance and so on. Gather these people (her relatives*) to witness your behavior. My guess if you are a bad Dad you wont find anybody.

And follow the advice you got here.