There are no rescue ships, the vast resources of Mission Control will be beyond reach and it'll take up to 20 minutes for your pleas to even reach Earth. You'll be a lot more comfortable about leaving the planet if you just don't plan on coming back. Don't worry about things you can't control. Such as radiation exposure. You're in space, an interplanetary traveler, an extraterrestrial being.
Dangers lurk beyond the planet's atmospheric womb.
Solar flares and cosmic rays are not kind to carbon-based life forms. If you want to worry, try to figure out what that humming sound is in your oxygen generator. Make sure you're compatible with your crewmates. To really do the trip right, you'll want a crew of ten or even 100. That way everybody can naturally sort out and seek out their companions, colleagues and lovers the same way people do on Earth.