ABS light and brake light intermittently come on and off consistently.

[flemdog3533]

After I start my pickup it idles just fine. When I put it into drive and start driving, the ABS light and the brake light come on along with my alarm and the pickup wants to stall out but will continue to run if I have the RPMs up high enough. The radio well also cut out when this happens. I just put in a new ignition switch in hopes that was the problem. That was not it. I just put a new alternator in also. I have checked all my grounds and they all seem to be good. Anybody have any ideas? I'm desperate.