Two gay men in a relationship bought a condominium in 2007 for $195,000 in the state of North Carolina.

At closing table they decided to deed it Joint Tenancy - Right of Survivorship

They have decided to end their relationship in 2011.

Information regarding financials:

(Co-owner #1)
-Obtained loan qualification independently, no need for co-signer
-Put down $5k in earnest money
-Used that as the downpayment at closing
-Closed on a mortgage loan for $190,000 and has made every payment for 4 years. Is the only name listed on the loan.
-Has paid 100% of yearly property taxes, it's rolled into his mortgage.
-Has paid 100% of the monthly HOA/POA maintenance fees, all upkeep, all improvements, all furnishings, all utility bills, insurance, etc
-Considers this his permanent residence and still occupies the home

(Co-owner #2)
-Has never contributed any money towards the property, in any way shape or form
-Voluntarily relinquished his key and has moved out.

Since relationship has dissolved, Co-owner #2 has threatened to pursue "his half" of the property.

What are Co-owner #1's options at this point?

1) Anybody have some advice on the likelihood of getting a judge to determine the property is his and remove Co-owner #2 from the deed, based on these financials, taxes, etc? Can you give any details on that process?

2) NC is a title theory state, and Co-owner #1's mortgage company holds the deed until the mortgage is paid. Would that help Co-owner #1's case? Anyone have any experience where a mortgage company intervened in a case like this to protect their loan from another owner?

3) Any opinions for Co-owner #1's likelihood of winning a suit asking for 50% of everything it cost to own/maintain the home for those 4 years?

4) Any other information that may be helpful would be greatly appreciated.