Weak signal on WNIC

My network interface card has recently come into some problems. The connection drops all the time, and for a good amount of time tonight it's been off completely. I will bullet point the info for ease of access.

• The network card has had a decent signal for a long time, and has recently (past few months) been degrading in signal quality/uptime.
• The plastic on the antennae has been broke for a while, but this hasn't seemed to change signal quality
• Sometimes the connection goes off completely, sometimes the connection is incredibly weak, sometimes it's perfectly fine. The times of when the connection dips or goes off seems completely random, sometimes when there are more people using the connection, it will actually be better.
• The connection is very unstable, it's very rare that I get a full day of good quality connection.
• I've set up a wireless hotspot with my phone, putting the phone right next to the router. My PC was able to connect to my phone, but not my router.
• Other people are able to connect to the router when I'm not.

Here's what I've done so far:

• Restarted the router.
• Unconnected and reconnected the wired connection between the router and the line.
• Restarted the network adapter many times.
• Flushed the DNS.
• Reset the IP config.
• Reinstalled drivers.

Could it be that my interface card as just packed in? I think something is wrong internally and it's not picking up weaker signals very well. But saying that, it was able to connect to my phone, even when it was the same distance away as my router.

Any help would be greatly appreciated :)
Thanks alot