Go for tamron, then you can put your 18-55 on add and get some money. You will feel the difference after first shots. 35 is a superb lens, but zoom is better. Tamron is more expensive, but in comparison - you will get nice wide angle outside and good zoom for portraits. Also it depends on your need for aperture. 1.8 vs 2.8. Also your bcamera body dont have built in focus motor. So about tamrons. There were three types of tamron lens. It was 2 generations. Second one have VR and all of them have built in focus. The first gen was seperated early ones didn't got focus, but after some time they decided to put focus motor. But both of first gen dont have VR.
P.S. I got both of them and using both but for different situations, both lenses are superb for their price. But if you are really not deep into photography go for tamron.