Answer: The entire forcing process is stressful on them. There is also the possibility that a variety was used that is good for forcing but less sturdy in terms of garden performance, so your results may or may not be satisfactory either way.
You can plant them now while they are blooming, even though that will result in a slightly higher planting level than would be preferred. Plant them at the same level or slightly deeper than they are in the pot. This allows the foliage to grow and ripen in the garden where it tends to be healthier and provides better long term results in my experience. If you do this, water as needed to keep the soil barely moist.
You could also keep them growing in the pot, but this is more stressful on the bulbs. Keep the soil barely moist, fertilize occasionally with a water soluble fertilizer for blooming plants, and provide very bright light. The goal is to keep the foliage growing for as long as possible. Once it has faded, stop watering. Unpot the bulbs and remove the withered leaves, store the bulbs in a cool and dry location with good air circulation until fall. Then, plant them as you would newly purchased bare tulip bulbs.
The foliage rebuilds the strength of the bulb and should be allowed to grow as long as possible, then allowed to yellow, ripen and wither naturally before it is removed.
Forcing tulips can be an exacting process, and the commercial operations use selected varieties, specially controlled temperatures, nutritional analyses and a greenhouse to produce the best results. At home, it is a bit more hit and miss.
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