Running in the forest alone is scary.
There are several options for running on trails with others in Cape Town. I am not sure what is happening upcountry but things must be moving along similar lines. Here is a short background to each so that you can narrow it down for yourself.

CRAG (Cape Runner’s Against Gravity) is the oldest and only dedicated trail running group in Cape Town. They do a big group run every Wed night in Cape Town and have just recently started a chapter in the Somerset West area. It is a very inclusive group run in that they wait for everybody to catch up and then carry on. There is a weekly newsletter with information on weekly runs and other events. Weekly runs start from a different venue each week. There are occasional weekend outings. Definitely for those just getting into trail while there are also some speedsters who attend. Mail crag-subscribe@yahoogroups.com

Tim Bellairs from VOB running club organises the trail runs for them. He sends out a few mails a week. They run on Saturday mornings and have started a Wed night run. I have not run with them on Wed night yet but they will almost definitely be faster than CRAG. http://www.vob.co.za/_trailrunning.asp

Patrick Cox from Celtics running club organises a Thursday run (mostly in summer). They have three different groups for different abilities and speeds. Visit http://www.celticharriers.co.za/index.php?option=com_content&view=article&id=15&Itemid=36 or mail Patrick to be added to his list mailto:patcox@ctjm.co.za

I would say that the most challenging option is the fast group on Thursdays- not out of reach for you at all. I don’t know about the VOB wed group but suspect that they are slightly slower. The CRAG group is very sociable.
All the above groups are very friendly and are happy to include everybody.

Douglas Rossouw of FHAC coordinates their trail runs. Mainly Saturday mornings and some midweek.
Mail douglasr@iafrica.com for their gatherings in the deep south.