Unfortunately, you have to pay alimony (called spousal maintenance in Colorado) for the length of time set forth in the decree or separation agreement. The decree or separation agreement will state how long you are required to pay. If the decree or separation agreement states that the maintenance is "non-modifiable," then you are stuck for the length stated. If the decree or separation agreement does not state "non-modifiable," you can petition the court for modification of maintenance if you have had at least a 10% change in income. You can also petition to terminate maintenance if your ex wife remarries or if she begins living in a common law relationship (broadly defined as holding themselves out as married, i.e. filing taxes jointly or claiming the other as a dependent on heath insurance. There is no period of time to establish common law an can, technically, be established after a week or month - although more difficult to prove).
If you have not had final orders at this time, the answer for length of maintenance depends on a varied number of factors. This includes the length of marriage and respective income of parties. I had a client who made $12,000 gross per month and the wife made $7,000. My client was in military and returning in a few months, which would result in a decrease of his income. Even though the parties had been married for 8 years, the court found no maintenance was required because wife made good money and had a lot of property to care for her needs. So you see, there are no hard and fast rules and whether you pay depends on a number of factors.
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