Gateway Model: M465-E Battery Problems

Hello everybody. I am new to these and need some help fixing my Gateway
laptop. I got this laptop for school about three years ago and have had
multiple problems with my battery before, but they were all easily
fixable. Not this time, apparently. My battery started losing its'
charge and when i plugged it in, it wouldn't take the charge from the
outlet. I tried every single outlet in the house to no avail. I also
replaced the AC adaptor with the same results. I'm wondering if i should
replace my battery or just get a new computer all together. Any
solutions would be greatly appreciated.

Thanks,
Nick